Ford training section2 diagnostic methods

SECTION Diagnostic Methods Contents Diagnostic Methods 2-1 Overview .2-1 Diagnostic Tools .2-2 Scan Tool Setup and Functionality 2-3 Vehicle Check And Preparation .2-4 Visual Checks .2-4 Vehicle Preparation 2-4 Quick Test Description 2-5 Clear the Continuous Diagnostic Trouble Codes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module (PCM) 2-8 Resetting The Keep Alive Memory (KAM) 2-9 On Board System Readiness (OSR) Test 2-10 Output State Control (OSC) 2-11 One Touch Integrated Start System .2-11 Output Test Mode (OTM) .2-12 Parameter Identification (PID) 2-13 Freeze Frame Data 2-22 2011Powertrain Control/Emissions Diagnosis, 8/2010 SECTION Diagnostic Methods Contents (Continued) Flash Electrically Erasable Programmable Read Only Memory (EEPROM) 2-24 Diagnostic Monitoring Test Results Mode 2-27 On Board Diagnostic (OBD) Drive Cycle 2-28 Intermittent Diagnostic Techniques 2-34 Recreating the Fault 2-34 Accumulating PCM Data 2-34 Peripheral Inputs 2-35 Comparing PCM Data 2-35 Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques 2-36 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-1 Table of Contents Diagnostic Methods Overview When following powertrain diagnostics on vehicles with on board diagnostic (OBD), the system may be checked by an off-board tester referred to as a scan tool This section contains information for carrying out diagnostics with a scan tool A scan tool has certain generic capabilities that are standard across the automotive industry in the United States and Canada All functions are selected from a menu Refer to the instruction manual provided by the tool manufacturer 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-2 Diagnostic Methods Diagnostic Tools Below is an equipment list with corresponding part numbers: REQUIRED EQUIPMENT: • Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool with functionality described under Scan Tool Setup and Functionality • Rotunda Smoke Machine, Fuel Evaporative Emission System Tester 218-00001 (522) or equivalent RECOMMENDED EQUIPMENT: • Rotunda Vacuum/Pressure Tester 164-R0253 or equivalent Range 0-101.3 kPa (0-30 in-Hg.) Resolution 3.4 kPa (1 in-Hg.) • Fuel Pressure Test Kit 310-D009 (D95L-7211A) or equivalent • Fuel Pressure Test Adapter 310-180 or equivalent • Digital Multimeter (DMM) FLU77-4 or equivalent • Adjustable Ignition Spark Tester THX404 or equivalent • Non-powered test lamp 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-3 Scan Tool Setup and Functionality Connect the scan tool to the data link connector (DLC) for communication with the vehicle The DLC is located in the driver side compartment under the steering column It is attached to the instrument panel and accessible from the driver seat The DLC is rectangular in design and capable of accommodating up to 16 terminals The connector has keying features to allow easy connection The required scan tool functions are described below: — monitor, record, and playback of parameter identification (PID) — freeze frame PID data — diagnostic test modes; self-test, clear diagnostic trouble codes (DTCs) — output state control — output test mode — resetting keep alive memory (KAM) — diagnostic monitoring test results (mode 6) for on board diagnostic (OBD) monitors — on board system readiness (OBD monitor completion status) Some of these functions are described in this section Refer to the scan tool manufacturer’s instruction manual for specific information on scan tool setup and operation International Standards Organization (ISO) 14229 DTC Descriptions The ISO 14229 DTC is a set of common requirements for diagnostic systems The scan tool displays a failure type and a status type with the DTC The types display additional information on the scan tool for the condition that set the DTC For a list of failure type descriptions, refer to Section 1, Powertrain Control Software, International Standards Organization (ISO) 14229 Diagnostic Trouble Code (DTC) Descriptions 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-4 Diagnostic Methods Vehicle Check And Preparation Before using the scan tool to carry out any test, refer to the important Safety Notice located at the beginning of this manual and the necessary visual checks listed below Visual Checks • Inspect the air cleaner and inlet duct • Check all engine vacuum hoses for damage, leaks, cracks, kinks, and proper routing • Check the electronic engine control (EEC) system wiring harness for proper connections, bent or broken pins, corrosion, loose wires, and proper routing • Check the powertrain control module (PCM), sensors, and actuators for physical damage • Check the engine coolant for proper level and mixture • Check the transmission fluid level and quality • Make all necessary repairs before continuing with the quick test Refer to Quick Test in this section for additional information Vehicle Preparation • Carry out all safety steps required to start and run vehicle tests Apply the parking brake, place the gear selector lever firmly into the PARK position on automatic transmission vehicles or NEUTRAL on manual transmission vehicles, and block the drive wheels • Turn off all electrical loads such as radios, lamps, A/C, blower, and fans • Start the engine (if the engine runs) and bring it up to the normal operating temperature before running the quick test 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-5 Quick Test Description Quick Test The quick test is divided into specialized tests: (1) Key On Engine Off (KOEO) On Demand Self-Test (2) Key On Engine Running (KOER) On Demand Self-Test (3) Continuous Memory Self-Test The quick test checks the integrity and function of the electronic engine control (EEC) system and outputs the test results when requested by the scan tool The quick test also provides a quick check of the powertrain control system, and is usually carried out at the start of each diagnostic procedure with all accessories off The quick test is also carried out at the end of most pinpoint tests for verification of the repair and to make sure no other concerns are incurred while repairing a previous concern A system pass is displayed when no diagnostic trouble codes (DTCs) are output and a scan tool communication error does not exist System pass means that hardware monitored by the powertrain control module (PCM) is functioning within the normal operating limits Only a system pass, a DTC, or an incomplete on board diagnostic (OBD) drive cycle is displayed For applications that use a stand-alone transmission control module (TCM) the PCM does not output TCM DTCs For TCM self-test and diagnostics, refer to the Workshop Manual Section 307-01 Automatic Transmission Key On Engine Off (KOEO) On Demand Self-Test The KOEO on demand self-test is a functional test of the PCM carried out on demand with the key on and the engine off This test carries out checks on certain sensor and actuator circuits A concern must be present at the time of testing for the KOEO self-test to detect the concern When a concern is detected, a DTC is output on the data link at the end of the test as requested by the scan tool Key On Engine Running (KOER) On Demand Self-Test The KOER on demand self-test is a functional test of the PCM carried out on demand with the key on, the engine running and the vehicle stopped A check of certain inputs and outputs is made during operating conditions and at a normal operating temperature The brake pedal position, transmission control, and the power steering tests are part of the KOER on demand self-test and must be carried out during this operation if applicable These are described below A concern must be present at the time of testing for the KOER on demand self-test to detect the concern When a concern is detected, a DTC is output on the data link at the end of the test as requested by the scan tool Brake Pedal Position (BPP) Test The BPP test checks the ability of the EEC system to detect a change of state in the BPP switch The brake pedal is briefly applied and released on all vehicles equipped with a BPP input This is done during a KOER on demand self-test 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-6 Diagnostic Methods Quick Test Description Power Steering Pressure (PSP) Test The PSP test checks the ability of the EEC system to detect a change in the power steering system fluid pressure The steering wheel is briefly turned at least 1/4 of a revolution on vehicles equipped with a PSP switch or sensor This is done during a KOER on demand self-test Transmission Control Switch (TCS) Test The TCS test checks the ability of the EEC system to detect a change of state in the TCS The switch is briefly cycled on all vehicles equipped with a TCS input This is done during a KOER on demand self-test Continuous Memory Self-Test The continuous memory self-test is a functional test of the PCM carried out under any condition (engine running or off) with the key on Unlike the KOEO and KOER self-tests, which can only be activated on demand, the continuous self-test is always active A concern does not need to be present when accessing continuous memory self-test DTCs, making the test valuable when diagnosing intermittent concerns The vehicle may need to be driven or the OBD drive cycle completed to allow the PCM to detect a concern Refer to On Board Diagnostic (OBD) Drive Cycle in this section for more information When a concern is stored in memory, a DTC is output on the data link when requested by the scan tool There are two types of continuous DTCs The first type is an emission-related code which illuminates the malfunction indicator lamp (MIL) in the instrument cluster The second is a non-emission related, non-MIL DTC which does not illuminate the instrument cluster indicator For emission-related MIL DTCs, the PCM stores the DTC in continuous memory when a concern is detected for the first time At this point the DTC does not illuminate the MIL and is considered a pending code The purpose of pending codes is to assist in repair verification by reporting a pending DTC after one drive cycle If the same concern is detected after the next drive cycle, the emission-related MIL code illuminates the MIL and sets both a confirmed MIL DTC and a permanent DTC The MIL remains illuminated even if the concern is intermittent A permanent DTC is stored until three consecutive passing drive cycles have been completed after a repair and the MIL turns off, or after a request to clear DTCs has been made using the scan tool and the next monitoring cycle has completed and passed for that DTC Confirmed emission-related MIL DTCs and any non-emission related, non-MIL DTCs are erased approximately 40 vehicle warm-up cycles after the concern was last detected, or if the DTCs are cleared by the scan tool Pending emission-related MIL DTCs that never detect a concern on a second consecutive drive cycle (and never light the MIL) are not retained in memory for any number of vehicle warm-up cycles; they are immediately cleared when the next monitoring cycle has completed and passed for that DTC, or until a request to clear DTCs has been made by the scan tool Any scan tool that meets OBD requirements can access the continuous memory to retrieve emission-related MIL DTCs However, not all scan tools access pending and non-emission related, non-MIL DTCs in the same way 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-7 Quick Test Description During most diagnostic procedures in this manual, it is required that all DTCs be retrieved and cleared Permanent DTCs cannot be directly cleared by the scan tool When a scan tool clears DTCs, pending and confirmed DTCs are immediately cleared Permanent DTCs will not clear until the next monitoring cycle has completed and passed for that DTC For additional information, refer to Section 1, Powertrain Control Software, Permanent Diagnostic Trouble Code (DTC) 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-8 Diagnostic Methods Clear the Continuous Diagnostic Trouble Codes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module (PCM) Description All on board diagnostic (OBD) scan tools support the clearing of continuous DTCs and resetting of emission monitors information in the PCM The clearing of the continuous DTCs allows the scan tool to command the PCM to clear and reset all emission-related diagnostic information On some vehicles, DTC P1000 is stored in the PCM until all the OBD system monitors or components have been tested to satisfy a drive cycle without any other concerns occurring For more information about a drive cycle, refer to On Board Diagnostic (OBD) Drive Cycle in this section The following events occur when the continuous DTCs and the emission monitors information is cleared from the PCM: • the number of DTCs is reset • the DTCs are cleared (on vehicles with permanent DTCs, additional vehicle operation is required to complete and pass the appropriate monitors to complete the clearing of permanent DTCs) • the freeze frame data is cleared • the diagnostic monitoring test results are reset • the status of the OBD system monitors is reset 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-25 Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Neutral Profile Correction — All Others In order for the misfire detection system to function correctly, any mechanical inaccuracies in the crankshaft position (CKP) sensor must be learned by the PCM This information is stored in non-volatile memory (NVM) in the PCM It is not cleared when the keep alive memory (KAM) is reset Neutral profile learning is accomplished using the scan tool any time a PCM is replaced It should also be relearned any time the CKP sensor or the crankshaft pulse wheel is replaced or major engine repairs have been completed To determine if the neutral profile learning has been completed, check the MP LRN parameter identification (PID) using the scan tool The PID should read YES if the neutral profile learning has been completed If the PID reads NO, complete the neutral profile learning prior to diagnosing any misfire DTCs Programming the VID Block for a Replacement PCM The VID block on a replacement PCM is blank and requires programming There are two procedures available The first is an automatic data transfer from the old PCM to the new PCM, the second is manual data entry into the new PCM Automatic data transfer is carried out if the old PCM is capable of communicating This is done by using a scan tool to retrieve data from the old PCM before removing it from the vehicle The stored data can be downloaded to the new PCM after it has been installed For Fiesta, the body control module communicates the vehicle identification number (VIN) to the PCM When a new PCM is installed, the PCM obtains the VIN the first time the ignition is turned to the ON position If there is a concern with the VIN not being received or being invalid, DTC P0630 is set Carry out manual data entry if the old PCM is damaged or incapable of communicating Remove and install a new PCM Using a compatible scan tool, select and carry out the module/parameter programming, referring to the scan tool manufacturer’s instruction manual Make certain that all parameters are included Failure to properly program tire size in revolutions per mile, (rev/mile equals 63,360 divided by the tire circumference in inches), axle ratio, 4x4 or 4x2, or MSOF and ESOF may result in DTCs P1635 and P1639 You may be instructed to contact the As-Built Data Center for the information needed to manually update the VID block with the scan tool Contact the center only if the old PCM cannot be used or the data is corrupt For Ford and Lincoln Mercury technicians, contact your National Hotline or the Professional Technician Society (PTS) web site for As-Built data listed under the Service Publications Index Non-Ford technicians use the Motorcraft web site at www.motorcraft.com From the Motorcraft home page, use the search function to find the Module Programming or As-Built Data For Ford and Lincoln Mercury technicians, check the Programmable Module Installation link on the PTS web site for quick Programmable Module data information by vehicle Making Changes to the VID Block A programmed PCM may require changes to be made to certain VID information to accommodate the vehicle hardware Refer to Module Reprogramming on the scan tool 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-26 Diagnostic Methods Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Making Changes to the PCM Calibration At certain times, the EEPROM needs to be completely reprogrammed This is due to changes made to the strategy or calibration after production or the need to reset the VID block because it has reached its limit Refer to PCM or Module Reprogramming on the scan tool 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-27 Diagnostic Monitoring Test Results Mode Mode allows access to the results of on board diagnostic (OBD) monitor diagnostic test results The test values are stored at the time of the particular monitor completion Refer to mode on the scan tool for test information 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-28 Diagnostic Methods On Board Diagnostic (OBD) Drive Cycle Description of On Board Diagnostic (OBD) Drive Cycle — Fiesta The following procedure is designed to execute and complete the OBD monitors To complete a specific monitor for repair verification, follow steps through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column For the EVAP monitor to run, the ambient air temperature must be between 3.75 to 40°C (38.8 to 104°F), and the altitude below 2,438 meters (8,000 feet) The OBD drive cycle is carried out using a scan tool Refer to the manufacturer’s instruction manual for each described function A detailed description for clearing the DTCs is found in this section Refer to Clear The Continuous Diagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The Powertrain Control Module (PCM) Drive Cycle Recommendations WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles Failure to follow these instructions may result in personal injury Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes Operating the throttle in a smooth fashion minimizes the time required for monitor completion The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable For best results, follow each of the following steps as accurately as possible: OBD Monitor Exercised Drive Cycle Preparation Drive Cycle Procedure Install the scan tool Turn the ignition ON with the engine OFF (do not cycle the ignition) If needed, select the appropriate vehicle and engine qualifier Clear the continuous DTCs and reset the emission monitors information in the PCM Purpose of Drive Cycle Procedure Resets the OBD monitor status Begin to monitor the following PIDs (if available): ECT, OUTDR TMP, EVAPDC, FLI and TP MODE Start the vehicle without returning the ignition to the OFF position Idle the vehicle for 30 seconds Drive at 77 to 104 km/h (48 to 65 mph) until the engine coolant temperature (ECT) is at least 76.7°C (170°F) (Continued) 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-29 On Board Diagnostic (OBD) Drive Cycle OBD Monitor Exercised Drive Cycle Procedure Purpose of Drive Cycle Procedure Prep for Monitor Entry Is the ambient air temperature (AAT) between 3.75 to 40°C (38.8 to 104°F)? If not the large leak and purge flow test will not complete It is not possible to bypass the EVAP monitor and complete the OBD Drive Cycle Entry condition for EVAP large leak and purge flow test HO2S Cruise between 1500 and 3000 rpm for at least minutes Allow engine to idle for minutes Accelerate to 70 km/h (43.5 mph) and hold for seconds at this speed Decelerate to 40 km/h (25 mph) with closed throttle (make sure the deceleration fuel cutoff mode has been entered) Executes the HO2S monitor Catalyst Ensure HHO2S monitor has completed Accelerate to 70 km/h (43.5 mph) and hold for seconds at this speed Decelerate to 40 km/h (25 mph) with closed throttle (make sure the deceleration fuel cutoff mode has been entered) At 40 km/h (25 mph) return to part throttle with the smallest possible throttle movement Repeat times Executes the catalyst monitor EVAP Cruise at speed greater than km/h (3.1 mph) for at least minutes Idle engine for at least minutes Executes the EVAP Large Leak and Purge Flow Monitor if ambient air temperature is between 3.75 to 40°C (38.8 to 104°F) Fuel Monitor Cruise with part throttle at 1500 - 2500 rpm for 20 minutes Allow vehicle to idle for 10 minutes Monitor will complete quicker if a fault is present Executes the fuel monitor Note: Executes the misfire monitor Misfire The misfire monitor will run before profile correction has been learned but for more accurate measurements profile correction should be learned Acceleratre to 104.6 km/h (65 mph), hold steady throttle for seconds, then decelerate to 64.4 km/h (40 mph) with closed throttle and no brakes (make sure the deceleration fuel cutoff mode has been entered) Repeat times Deceleration Fuel Shut Off Rear HO2S Monitor Accelerate to 104.6 km/h (65 mph), hold steady throttle for seconds, then decelerate to 64.4 km/h (40 mph) with closed throttle and no brakes (make sure the deceleration fuel cutoff mode has been entered) Repeat times Executes the deceleration fuel shut off rear HO2S monitor Readiness Check Access the On Board System Readiness (OBD monitor status) function on the scan tool Determine whether all noncontinuous monitors have completed Determines if any monitor has not completed With the scan tool, check for pending codes Conduct the normal repair procedures for any pending code concern Determines if a pending code is preventing the completion of the OBD drive cycle Pending Code Check (Continued) 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-30 Diagnostic Methods On Board Diagnostic (OBD) Drive Cycle OBD Monitor Exercised EVAP Small Leak Drive Cycle Procedure Note: Purpose of Drive Cycle Procedure Executes the small leak monitor Prior to checking for a small leak, the vehicle should be driven during the hottest part of the day before leaving for overnight soak A complete PCM power down must be completed prior to starting the engine for the drive cycle preperation drive After the ignition is turned OFF for the overnight soak the ignition must not be turned ON prior to starting the engine in the morning When starting the vehicle after the overnight soak the engine must be started after initial ignition ON (do not cycle the ignition) The small leak test result will be available 60 seconds after engine start At the end of EVAP large leak and purge flow test if no fault is found check that NVLD is closed and purge is active by checking the EVAP ACTIVE and EVAP SWITCH PIDs Turn the ignition OFF and continue to monitor the switch position PID Wait until the PCM powers down The NVLD switch position should remain closed until the PCM powers down To confirm a small leak the vehicle should be left outside overnight Description of On Board Diagnostic (OBD) Drive Cycle — All Others The following procedure is designed to execute and complete the OBD monitors To complete a specific monitor for repair verification, follow steps through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column For the EVAP monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F), and the altitude below 2,438 meters (8,000 feet) If the OBD monitors must be completed in these conditions, the powertrain control module (PCM) must detect them once (twice on some applications) before the EVAP monitor can be bypassed and OBD monitors readied The EVAP bypassing procedure is described in the following drive cycle The OBD drive cycle is carried out using a scan tool Refer to the manufacturer’s instruction manual for each described function 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-31 On Board Diagnostic (OBD) Drive Cycle A detailed description for clearing the DTCs is found in this section Refer to Clear The Continuous Diagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The Powertrain Control Module (PCM) Drive Cycle Recommendations WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles Failure to follow these instructions may result in personal injury Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes Operating the throttle in a smooth fashion minimizes the time required for monitor completion The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable The evaporative monitor can operate only during the first 30 minutes of engine operation When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh When bypassing the EVAP engine soak times, the PCM must remain powered (key ON) after clearing the continuous DTCs and relearning emission diagnostic information For best results, follow each of the following steps as accurately as possible: OBD Monitor Exercised Drive Cycle Preparation Drive Cycle Procedure Note: To bypass the EVAP soak timer (normally hours), the PCM must remain powered after clearing the continuous DTCs and resetting the emission monitors information in the PCM Purpose of Drive Cycle Procedure Bypasses the engine soak timer Resets the OBD monitor status Install the scan tool Turn the key ON with the engine OFF Cycle the key off, then on If needed, select the appropriate vehicle and engine qualifier Clear the continuous DTCs and reset the emission monitors information in the PCM Begin to monitor the following PIDs (if available): ECT, EVAPDC, FLI and TP MODE Start the vehicle without returning the key to the OFF position (Continued) 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-32 Diagnostic Methods On Board Diagnostic (OBD) Drive Cycle OBD Monitor Exercised Drive Cycle Procedure Purpose of Drive Cycle Procedure Idle the vehicle for 15 seconds Drive at 77 to 104 km/h (48 to 65 mph) until the engine coolant temperature (ECT) is at least 76.7°C (170°F) Prep for Monitor Entry Is the intake air temperature (IAT) between 4.4 and 37.8°C (40 and 100°F)? If not, complete the following steps, but note that step 14 is required to bypass the EVAP monitor and complete the OBD drive cycle Engine warm-up and provides IAT input to the PCM HO2S Cruise at 77 to 104 km/h (48 to 65 mph) for at least minutes Executes the HO2S monitor EVAP Cruise at 77 to 104 km/h (48 to 65 mph) for 10 minutes (avoid sharp turns and hills) NOTE: To initiate the monitor, the throttle should be at part throttle, EVAPDC must be greater than 75%, and FLI must be between 15 and 85%, and for fuel tanks over 25 gallons FLI must be between 30 and 85% Executes the EVAP monitor if the IAT is between 4.4 to 37.8°C (40 to 100°F) Catalyst Drive in stop and go traffic conditions Include different constant cruise speeds, ranging from 40 to 72 km/h (25 to 45 mph) over a 10 minute period Executes the catalyst monitor EGR From a stop, idle for 30 seconds, accelerate to 72 km/h (45 mph) at 1/2 to 3/4 throttle, cruise at steady throttle for minute Repeat idle, acceleration and cruise times Executes the EGR monitor CCM (Engine) Bring the vehicle to a stop Idle with the transmission in drive (neutral for M/T) for minutes Executes the idle air control (IAC) portion of the comprehensive component monitor (CCM) CCM (Transmission) 10 For M/T, accelerate from to 80 km/h (0 to 50 mph), and continue to step 11 For A/T, from a stop and in overdrive, moderately accelerate to 80 km/h (50 mph) and cruise for at least 15 seconds Stop the vehicle and repeat without overdrive to 64 km/h (40 mph) cruising for at least 30 seconds While at 64 km/h (40 mph), activate the overdrive, accelerate to 80 km/h (50 mph) and cruise for at least 15 seconds Stop for at least 20 seconds and repeat step 10 five times Executes the transmission portion of the CCM Misfire, Fuel and Deceleration Fuel Shut Off Rear HO2S Monitors 11 From a stop, accelerate to 104 km/h (65 mph), hold steady throttle for seconds, then decelerate at closed throttle to 64 km/h (40 mph) (no brakes), accelerate from 64 Km/h (40 mph) to 104 Km/h (65 mph), hold steady throttle for seconds, repeat deceleration times Allows learning for the misfire monitor, and completion of the deceleration fuel shut off rear HO2S monitor Readiness Check 12 Access the On Board System Readiness (OBD monitor status) function on the scan tool Determine whether all non-continuous monitors have completed If not, go to step 13 Determines if any monitor has not completed (Continued) 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-33 On Board Diagnostic (OBD) Drive Cycle OBD Monitor Exercised Drive Cycle Procedure Purpose of Drive Cycle Procedure Pending Code Check and EVAP Monitor Bypass Check 13 With the scan tool, check for pending codes Conduct the normal repair procedures for any pending code concern Otherwise, repeat any incomplete monitor If the EVAP monitor is not complete and the IAT was out of the 4.4 to 37.8°C (40 to 100°F) temperature range in step 4, or the altitude is over 2438 m (8000 ft.), the EVAP bypass procedure must be followed Go to Step 14 Determines if a pending code is preventing the completion of the OBD drive cycle EVAP Monitor Bypass 14 Park the vehicle for a minimum of hours Repeat steps through 11 Do not repeat step Allows the bypass counter to increment to 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-34 Diagnostic Methods Intermittent Diagnostic Techniques Intermittent diagnostic techniques help find and isolate the root cause of intermittent concerns associated with the electronic engine control (EEC) system The information is organized to help find the concern and carry out the repair The process of finding and isolating an intermittent concern starts with recreating a fault symptom, accumulating powertrain control module (PCM) data, and comparing that data to typical values, then analyzing the results Refer to the scan tool manufacturer’s instruction manual for the functions described below Before proceeding, be sure that: • Customary mechanical system tests and inspections not reveal a concern Mechanical component conditions can make a PCM system react abnormally • Technical Service Bulletins (TSBs) and On-line Automotive Service Information System (OASIS) messages, if available, are reviewed • Quick Test and associated diagnostic subroutines have been completed without finding a concern, and the symptom is still present Recreating the Fault Recreating the concern is the first step in isolating the cause of the intermittent symptom A thorough investigation should start with the customer information worksheet located in the back of this manual If freeze frame data is available, it may help in recreating the conditions at the time of a malfunction indicator lamp diagnostic trouble code (MIL DTC) Listed below are some of the conditions for recreating the concern: CONDITIONS TO RECREATE FAULT Engine Type Conditions Non-Engine Type Conditions Engine Temperature Ambient Temperature Engine RPM Moisture Conditions Engine Load Road Conditions (smooth-bumpy) Engine idle/accel/deceleration Accumulating PCM Data PCM data can be accumulated in a number of ways This includes circuit measurements with a digital multimeter (DMM) or scan tool parameter identification (PID) data Acquisition of PCM PID data using a scan tool is one of the easiest ways to gather information Gather as much data as possible when the concern is occurring to prevent improper diagnosis Data should be accumulated during different operating conditions and based on the customer description of the intermittent concern Compare this data with the known good data values Refer to Section 6, Typical Diagnostic Reference Values This requires recording data in four conditions for comparison: 1) KOEO, 2) Hot Idle, 3) 48 km/h (30 mph), and 4) 89 km/h (55 mph) 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-35 Intermittent Diagnostic Techniques Peripheral Inputs Some signals may require certain peripherals or auxiliary tools for diagnosis In some cases, these devices can be inserted into the measurement jacks of the scan tool or DMM For example, connecting an electronic fuel pressure gauge to monitor and record the fuel pressure voltage reading and capturing the data would help find the fault Comparing PCM Data After the PCM values are acquired, it is necessary to determine the concern area This typically requires the comparison of the actual values from the vehicle to the typical values from Section Refer to Section 6, Typical Diagnostic Reference Values The charts apply to different vehicle applications (engine, model, transmission) Analyzing PCM Data Look for abnormal events or values that are clearly incorrect Inspect the signals for abrupt or unexpected changes For example, during a steady cruise most of the sensor values should be relatively stable Sensors such as throttle position (TP) and mass air flow (MAF), as well as an RPM that changes abruptly when the vehicle is traveling at a constant speed, are clues to a possible concern area Look for an agreement in related signals For example, if the APP1, APP2, or APP3, changes during acceleration, a corresponding change should occur in RPM and SPARK ADV PID Make sure the signals act in proper sequence An increase in RPM after the TP1 and TP2 increases is expected However, if the RPM increases without a TP1 and TP2 change, a concern may exist Scroll through the PID data while analyzing the information Look for sudden drops or spikes in the values 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-36 Diagnostic Methods Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques The Adaptive Fuel DTC Diagnostic Techniques help isolate the root cause of the adaptive fuel concern Before proceeding, attempt to verify if any driveability concerns are present These diagnostic aids are meant as a supplement to the pinpoint test steps in Section For a description of fuel trim, refer to Section 1, Powertrain Control Software, Fuel Trim Obtain Freeze Frame Data Freeze frame data is helpful in duplicating and diagnosing adaptive fuel concerns The data (a snapshot of certain parameter identification (PID) values recorded at the time the DTC is stored in Continuous Memory) is helpful to determine how the vehicle was being driven when the concern occurred, and is especially useful on intermittent concerns Freeze frame data, in many cases, helps isolate possible areas of concern as well as rule out others Refer to Freeze Frame Data in this section for a more detailed description of this data Using the LONGFT1 and LONGFT2 (Dual Bank Engines) PIDs The LONGFT1 and LONGFT2 PIDs are useful for diagnosing fuel trim concerns A negative PID value indicates fuel is being reduced to compensate for a rich condition A positive PID value indicates fuel is being increased to compensate for a lean condition It is important to know there is a separate LONGFT value used for each RPM and load point of engine operation When viewing the LONGFT1 and LONGFT2 PIDs, the values may change a great deal as the engine is operating at different RPM and load points This is because the fuel system may have learned corrections for fuel delivery concerns that can change as a function of engine RPM and load The LONGFT1 and LONGFT2 PIDs display the fuel trim currently being used at that RPM and load point Observing the changes in LONGFT1 and LONGFT2 can help when diagnosing fuel system concerns For example: • A contaminated mass air flow (MAF) sensor results in matching LONGFT1 and LONGFT2 correction values that are negative at idle (reducing fuel), but positive (adding fuel) at higher RPM and loads • LONGFT1 values that differ greatly from LONGFT2 values rule out concerns that are common for both banks (for example, fuel pressure concerns, MAF sensor, etc can be ruled out) • Vacuum leaks result in large rich corrections (positive LONGFT1 and LONGFT2 values) at idle, but little or no correction at higher RPM and loads • A plugged fuel filter results in no correction at idle, but large rich corrections (positive LONGFT1 and LONGFT2 values) at high RPM and load Resetting Long Term Fuel Trims Long term fuel trim corrections are reset by resetting the keep alive memory (KAM) Refer to Resetting The Keep Alive Memory (KAM) in this section After making a fuel system repair, reset the KAM For example, if dirty or plugged injectors cause the engine to run lean and generate rich long term corrections, installing new injectors and not resetting the KAM causes the engine to run very rich The rich correction eventually leans out during closed loop operation, but the vehicle may have poor driveability and high carbon monoxide (CO) emissions while it is learning 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-37 Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques DTCs P0171 and P0174 System Too Lean Diagnostic Aids Note: If the system is lean at certain conditions, then the LONGFT PID would be a positive value at those conditions, indicating that increased fuel is needed The ability to identify the type of lean condition causing the concern is crucial to a correct diagnosis Air Measurement System With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the powertrain control module (PCM) is not able to compensate enough to correct for the condition One possibility is the mass of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM For example, with a contaminated MAF sensor, the engine runs lean at higher RPM because the PCM delivers fuel for less air than is actually entering the engine Example: • The MAF sensor measurement is inaccurate due to a corroded connector, contaminated or dirty connector A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel) Vacuum Leaks and Unmetered Air With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition This condition can be caused by unmetered air entering the engine, or due to a MAF concern In this situation, the volume of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM Vacuum leaks normally are most apparent when high manifold vacuum is present (for example, during idle or light throttle) If freeze frame data indicates the fault occurred at idle, a check for vacuum leaks and unmetered air might be the best starting point For example, loose, leaking or disconnected vacuum lines, intake manifold gaskets or O-rings, throttle body gaskets, brake booster, air inlet tube, a stuck, frozen or aftermarket positive crankcase ventilation (PCV) valve, and unseated engine oil dipstick Insufficient Fueling With this condition, the engine runs lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition This condition is caused by a fuel delivery system concern that restricts or limits the amount of fuel being delivered to the engine This condition is normally apparent as the engine is under a heavy load and at high RPM, when a higher volume of fuel is required If the freeze frame data indicates the concern occurs under a heavy load and at higher RPM, a check of the fuel delivery system (checking fuel pressure with engine under a load) is the best starting point Examples of this include: • low fuel pressure (fuel pump, fuel filter, fuel leaks, restricted fuel supply lines) • fuel injector concerns Exhaust System Leaks 2011Powertrain Control/Emissions Diagnosis, 8/2010 2-38 Diagnostic Methods Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques In this type of condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio) because the fuel control system is adding fuel to compensate for a perceived (not actual) lean condition This condition is caused by the heated oxygen sensor (HO2S) sensing the oxygen (air) entering the exhaust system from an external source The PCM reacts to this exhaust leak by increasing fuel delivery This condition causes the exhaust gas mixture from the cylinder to be rich Examples of this include: • exhaust system leaks upstream or near the HO2S • cracked/leaking HO2S boss DTCs P0172 and P0175 System Too Rich Diagnostic Aids Note: If the system is rich at certain conditions, then the LONGFT PID would be a negative value at that airflow, indicating that decreased fuel is needed System rich concerns are caused by fuel system concerns, although the MAF sensor and base engine (for example, engine oil contaminated with fuel) should also be checked Air Measurement System With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition One possibility, the MAF sensor measurement is inaccurate due to a corroded connector, contamination or dirt on the MAF screen or elements A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel) Fuel System With this condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio), if the PCM is not able to compensate enough to correct for the condition This situation causes a fuel delivery system that is delivering excessive fuel to the engine Examples of this include: • fuel pressure regulator (mechanical returnless fuel systems) causes excessive fuel pressure (system rich at all airflows), fuel pressure is intermittent, going to pump deadhead pressure, then returning to normal after the engine is turned off and restarted • fuel injector leaks (injector delivers extra fuel) • evaporative emission (EVAP) canister purge valve leak (if the canister is full of vapors, introduces extra fuel) • fuel rail pressure (FRP) sensor (electronic returnless fuel systems) concern causes the sensor to indicate a lower pressure than actual The PCM commands a higher duty cycle to the fuel pump driver module (FPDM), causing high fuel pressure (system rich at all airflows) Intake Air System 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-39 Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques A restriction within any of the following components may be significant enough to affect the ability of the PCM adaptive fuel control • air inlet tube • air cleaner element • air cleaner assembly • resonators • clean air tube Base Engine Engine oil contaminated with fuel can contribute to a rich-running engine 2011Powertrain Control/Emissions Diagnosis, 8/2010 ... (DTC) Diagnostic Techniques 2-36 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-1 Table of Contents Diagnostic Methods Overview When following powertrain diagnostics... pressure Ford PID List Note: This is not a complete list of Ford PIDs available This is a list of Ford PIDs in this manual 2011Powertrain Control/Emissions Diagnosis, 8/2010 Diagnostic Methods. .. Control/Emissions Diagnosis, 8/2010 Diagnostic Methods 2-27 Diagnostic Monitoring Test Results Mode Mode allows access to the results of on board diagnostic (OBD) monitor diagnostic test results The