Toyota training 973a hi tech update engine technician handbook 01 08 09

Advanced Engine Control Hi-Tech Update 973A Technician Handbook © 2009 Toyota Motor Sales, U.S.A., Inc All rights reserved This book may not be reproduced or copied, in whole or in part by any means, without the written permission of Toyota Motor Sales, U.S.A., Inc Hi-Tech Update - Advanced Engine Control Technician Handbook Table of Contents Course L973A:Introduction to Advanced Engine Control I Section Accumulated Emissions FTP Emission Levels CAN OBD II Update Interpreting Non-Continuous Readiness Monitor Status and Results Readiness Monitor Test Results Monitor Information -Key ON, Engine OFF Monitor Information -Engine Running Readiness Monitor Test Details 10 Readiness MonitorTest Details -DTCs Cleared 11 Permanent DTC 12 Permanent DTC 13 Permanent DTC -Three Trip Clear 14 Permanent DTC -One Trip Clear 15 Permanent DTC 16 Calculated Load(Calc Load) 17 Vehicle Load -Absolute Load 18 Air Flow 19 MIL ON Data List 20 Section - Misfire 21 Misfire Detection 22 Misfire Data List 23 continued 24 Misfire Margin 25 Cat OT MF/FC 26 Cylinder Misfire Rate (Count) & EWMA Misfire 27 continued 28 Example of EWMA Misfire Count 29 Cylinder Speed Data List 30 Section - Overview of Sensor Operation 31 Circuit Configuration of Mass Air Flow Meter 32 A/F Sensor 33 Current and Voltage Characteristic 34 Technical Training Hi-Tech Update - Advanced Engine Control Technician Handbook A/F Sensor Circuit 35 Comparisons between A/F Sensor and O2 Sensor 36 O2 Sensor Construction 37 CO and O2 Effect on Oxygen Sensor 38 Super Stability O2 Sensor 39 Heater Circuit 40 Heater Operation 41 Temperature Detection 42 A/F Sensor Circuit 43 A/F Ratio Sensor Pumping Circuit 44 O2 Sensor Circuit 45 O2 Sensor Temperature and Impedance 46 Section - Overview of Fuel Injection & Catalytic Converter 47 Stoichiometric Lamda Air/Fuel Ratio 48 Oxygen Storage Capacity (OSC) 49 Oxygen Storage Capacity (OSC) 50 Fuel Injection Duration 51 Fuel Trim 52 Fuel Trim Response 53 Fuel Trim Diagnosis 54 Fuel Trim Parameters and Values 55 Fuel Trim Diagnosis Tips 57 Relationship between Fuel Injection Duration and MAF Malfunction or Air Leak 58 MAF Air Flow Comparison Check w/Load 59 MAF Air Flow Comparison Check wo/Load 60 Airflow-Free VG Check 61 Characteristics of MAF Sensors 62 Relationship between Fuel Injection Duration and Fuel System Malfunction 64 Fuel Trim DTC(s) with Driveability Issues 65 Section - Catalytic Converter & A/F - O2 Sensor Monitors 66 AF Sensor Pumping Circuit 67 AF Sensor Circuit 68 O2 Sensor DTCs by Impedance Detection 69 O2 Sensor Circuit 70 O2 Sensor Temperature and Impedance 71 Technical Training Hi-Tech Update - Advanced Engine Control Technician Handbook Active A/F Control Sequence 72 Active AF Type 73 Catalyst Monitor 73 A/F Sensor 74 Active AF Control for AF Sensor Response 75 AF Sensor Response – DTC P2A00, P2A03 76 Active AF Control 77 Active AF Control for O2 Sensor & Catalytic Converter Response 78 Good O2 Sensor Response Rich to Lean 79 Good O2 Sensor Response Lean to Rich 80 Active AF Control Capture – O2 Sensor Response 81 P0136 O2 Sensor Circuit Abnormal Voltage 82 HO2 Sensor Circuit Malfunction 83 P0137 O2 Sensor Circuit Low Voltage 84 P0138 O2 Sensor Circuit High Voltage 85 HO2 Sensor Circuit 86 P0138 Stuck Lean AF Sensor 87 Injector Volume & AF Active Tests 88 P0138 – Malfunctioning AF Sensor 89 P0138 – Check for Malfunctioning AF Sensor 90 CO and O2 Effect on Oxygen Sensor 91 Active AF Control 92 Good Catalyst Response 93 Good Catalyst Response 94 Active AF Control Capture – Good Catalyst Response 95 Deteriorated Catalyst – Active AF Control 96 Active AF Control Capture – Failed Catalyst Response 97 Catalyst Monitoring System 98 Interpreting Catalyst OSC Test Details 99 Conditioning for Sensor Testing 100 A/F Ratio Sensor Rationality Check 101 AF Sensor Stuck Lean P2195 102 Drive Pattern 103 Drive Pattern 104 Inspection 105 Heated Oxygen Sensor Voltage Fuel Cut (DTC P0139 and P0159) 107 Technical Training Hi-Tech Update - Advanced Engine Control Technician Handbook Section - EVAP Purge Operation and Monitor 108 The Way Purge Density Is Learned 109 Purge Control 110 EVAP Purge Flow and Purge Density Learn Value 111 Calculation Example of Purge Density Learn Value 112 Engine Running Purge Flow Monitor 113 Knock Control System 114 Knocking Threshold and Fuel Consumption / Engine Output 115 Resonant Knock Sensor 116 Flat Response Knock Sensor 117 Switching of Knock Detection Filter Frequencies 118 Knock Judgment .119 Calculation Example of a Knock Value( renewed every 0.5 seconds approximately) 120 Learning Ranges 121 Relationship Among Timing, Knock Correct Learn Value, and Knock Feedback Value 122 Relationship Among Timing, Knock Correct Learn Value, and Knock Feedback Value 123 Conditions under which a Knocking Problem Occurs 124 Unit of MAF 125 Technical Training Hi-Tech Update - Advanced Engine Control Course 973A: Introduction to Advanced Engine Control Technical Training Technician Handbook The technician will be able to determine the condition of advanced CAN OBDII engine control systems based on verified diagnostic repair procedures and technical information using: monitored test results, diagnostic tools, and service literature I Hi-Tech Update - Advanced Engine Control Technician Handbook Complete Incomplete Monitor Status Permanent DTC Calculated load Vehicle Load Atmospheric Pressure Section Objectives Technical Training CAN OBDII Update • Determine the condition of a vehicle based on readiness monitor results, data list parameters, and status of DTCs • Clear Permanent DTCs • Use new data list parameters for MIL ON diagnosis Hi-Tech Update - Advanced Engine Control Accumulated Emissions FTP Technician Handbook FTP stands for Federal Test Procedure Note that emissions are high, particularly NOx, at start up Technical Training Hi-Tech Update - Advanced Engine Control Emission Levels Technician Handbook The above emission labels are California labels The Federal equivalents are: Tier Bin = LEV II ULEV Tier Bin = LEV II SULEV DTCs are required to set according to the applicable emission standard NMOG stands for Non-methane Organic Gases Technical Training Technician Handbook Hi-Tech Update - Advanced Engine Control Status Status Misfire Ready Available Fuel System Ready Available Composition Parts Ready Available Catalyst Efficiency Ready Complete Heated Catalyst Not Ready N/A Evaporative System Ready Incomplete Secondary Air System Ready N/A A/C System Not Ready N/A O2 Sensor Ready Incomplete Pass O2 Sensor Heater Ready Complete Pass EGR Not Ready N/A Monitor Interpreting Non-Continuous Readiness Monitor Status and Results Result Details Summary Continuous Monitor Monitor ran and passed this trip Pass N/A Fail Monitor ran and failed this trip N/A Monitor has not finished testing N/A Monitor is not supported Readiness Monitors The goal of the OBD II regulation is to provide the vehicle with an on-board diagnostic system capable of continuously monitoring the efficiency of the emission control systems, and to improve diagnosis and repair efficiency when system failures occur On-board tests are performed by the ECM Two types of on-board test monitoring are supported: continuous and non-continuous These are known as readiness monitors, or simply monitors If a readiness monitor fails, DTC(s) specific to the failure(s) are set Interpreting Non-Continuous Readiness Monitors Status and Results Understanding Readiness Monitors Status and Results will help to duplicate concerns and verify repairs The following is a guide to interpret non-continuous Readiness Monitors Status and Results: Complete, Pass If Status (OBD II), Status (CAN OBD II) displays Complete and Result displays Pass then the monitor completed testing and passed this trip Check Test Details for all Readiness Monitors to ensure tests are passing well within the Min Limit and Max Limit thresholds (see Readiness Monitors Test Details topic for more information) Incomplete, Fail If Status (OBD II), Status (CAN OBD II) displays Incomplete and Result displays Fail then the monitor ran and failed this trip An issue Technical Training Technician Handbook Hi-Tech Update - Advanced Engine Control EVAP Purge Flow of 1%… Indicates a condition in which the ratio of purge air to MAF is one percent MAF 99% Purge Density Learn Value… Indicates the extent of effects of purge air on A/F Short FT* (%) EVAP purge flow 1% 1% Purge air The A/F in red zone is unknown MAF 99% 1% Purge air Fuel is injected against 99% of air so that A/F in blue zone is “14.7” EVAP Purge Flow and Purge Density Learn Value Technical Training 110 Technician Handbook Hi-Tech Update - Advanced Engine Control • When the A/F of purge air to fuel is 14.7 (Stoichiometric A/F) MAF 99% Purge air 14.7 14.7 Short FT (%) Stoichiometric A/F 1% EVAP purge flow 1% = 0% 1% = 0%/% Basic injection quantity is correct • If A/F of purge air to fuel is 0.0 (insufficient fuel) MAF 99% Lean 1% Purge air 0.0 14.7 Short FT (%) 1% of fuel is insufficient EVAP purge flow 1% = 1% 1% = 1%/% Fuel added • If A/F of purge air to fuel is 1.47:1 (excessive fuel) MAF 99% 14.7 Rich 1% Purge air 1.47 The amount of fuel contained in 1% is 10% of air volume Short FT (%) EVAP purge flow 1% = -10% 1% = -10%/% Fuel subtracted Calculation Example of Purge Density Learn Value Technical Training 111 Hi-Tech Update - Advanced Engine Control Engine Running Purge Flow Monitor Technician Handbook DTC P0441 The 1st monitor While the engine is running and the EVAP VSV (vacuum Switching Valve) is ON (open), the ECM monitors the purge flow by measuring the EVAP pressure change If negative pressure is not created, the ECM begins the 2nd monitor The 2nd monitor The vent valve is turned ON (closed) and the EVAP pressure is then measured If the variation in the pressure is less than 0.5 kPa (3.75 mmHg), the ECM interprets this as the EVAP VSV being stuck closed, and illuminates the MIL and sets DTC P0441 (2 trip detection logic) Atmospheric pressure check: In order to ensure reliable malfunction detection, the variation between the atmospheric pressure, before and after conduction of the purge flow monitor, is measured by the ECM Technical Training 112 Hi-Tech Update - Advanced Engine Control Technician Handbook Operation Data List Parameters Knock Control System Technical Training 113 Technician Handbook Hi-Tech Update - Advanced Engine Control Optimal ignition timing High Low Engine output Fuel consumption Retard Ignition timing Advance (Constant engine load and speed) Knocking Threshold and Fuel Consumption / Engine Output Technical Training Knocking threshold Knocking is a phenomenon in which the air fuel mixture in the combustion chamber self ignites, burning spontaneously due to heat sources such as carbon From a knocking engine, noises such as “tapping, clacking, or cracking” will be heard • The more advanced the ignition timing is, the more likely knocking is to occur Excessive knocking cannot only deteriorate fuel economy and engine output but adversely affect the engine condition as well In the worst case, it could even cause melting damage to the valves, pistons, spark plugs, etc On the other hand, improvement of both fuel economy and engine output can also come from the ignition timing near the threshold point of knocking where only a slight amount of knocking occurs (See figure below) • It is best, therefore, that the ignition timing of an engine be set close to the threshold point of knocking.In reality, however, the threshold point of knocking differs among engines due to a number of factors such as operating conditions, fuel used, and deterioration over time • In the process of knock control, in order to attain an optimal timing of ignition for operating conditions, knocking is searched for by use of a knock sensor attached to the cylinder block and once knocking is detected, the ignition timing is retarded to bring it as close to the knocking threshold point as possible 114 Technician Handbook Hi-Tech Update - Advanced Engine Control High Mounts to cylinder block Deflection caused by cylinder block vibrations Piezoceramic Vibrating plate Piezoceramic Vibrating plate Resonant Knock Sensor Technical Training Output (V) Low Cylinder block Low Frequency High Output Characteristics: Resonant Type Knock Sensor Fading away 115 Technician Handbook Hi-Tech Update - Advanced Engine Control High Weight Judgment point Piezoceramic Cylinder block side Piezoceramic Weight Output (V) Low Low Pressure caused by cylinder block vibrations Cylinder block Flat Response Knock Sensor Frequency High Output Characteristics: Flat Response Knock Sensor The vibrations from the cylinder block will act on the weight by way of the piezoceramic Because the inertial force causes a delay in the response of the weight, the piezoceramic placed between the cylinder block and the weight is pressurized, which causes a voltage to be generated Unlike the resonant knock sensor, the flat response knock sensor can maintain virtually constant output characteristics in all frequency ranges As a result, the engine ECU can detect every knocking frequency targeted, thus ensuring a higher accuracy in knock detection Technical Training 116 Technician Handbook Hi-Tech Update - Advanced Engine Control 3-level switching High Judgment point Output (V) Low Low Switching of Knock Detection Filter Frequencies Technical Training Frequency High Switching the Knock Detection Filter Frequency (for Flat Response Knock Sensor Only) • The knocking frequency changes as the engine speed and engine load • On systems using a flat knock sensor for knock sensor, detection of an appropriate knocking magnitude is achieved in any operating range, for the knock detection filter frequency (knock detection frequency property) switches between three levels (for example, 5.8 kHz, kHz, 11.7 kHz) according to engine conditions 117 Technician Handbook Hi-Tech Update - Advanced Engine Control Knock judgment line Knocking Abnormal engine noise Knock signal Not detected Out of knock judgment zone Engine ECU detects knock Knock judgment zone Knock judgment zone Knock Signal and Knock Judgment Knock Judgment Technical Training • Aside from a knocking noise, an engine is subject to a wide variety of similar vibration noises, which include injector operating noise and valve opening/closing noise Besides, in the case of a VVT-i engine, the valve opening/closing timing (valve seating noise) is changing • The ECM assigns a knock judgment enable zone to each cylinder so that only knocking vibrations can be isolated for detection of knock for each cylinder • The detected knock signal is judged to be in one of the three levels of knocking magnitude (None, Minor, Major) according to the “knock judgement level” preset in the engine ECU 118 Technician Handbook Hi-Tech Update - Advanced Engine Control Status and Repeats of Knocking Initiation No knocking Knocking Knocking Magnitude Low High +0.23°CA Sporadic knocking -0.23°CA -0.46°CA Multi-cylinder knocking -0.46°CA -0.92°CA Multi-cylinder knocking (high rev.) -0.46°CA -0.92°CA Continuous knocking in a single cylinder -0.92°CA -1.84°CA +: Advance; -: Retard Calculation Example of a Knock Value( renewed every 0.5 seconds approximately) Technical Training 119 Technician Handbook Hi-Tech Update - Advanced Engine Control High speed range Medium speed range 4300 4500 (rpm) Low speed range* 2700 2900 Values are illustrative *On some engines, knocking control is unavailable in low speed range with light load Learning Ranges Technical Training 120 Technician Handbook Hi-Tech Update - Advanced Engine Control For example, ignition timing at 200 rpm Advance Ignition timing A B Max advance limit Ignition timing Max retard limit Engine load High A: Knock Feedback Value B: Knock Correct Learn Value : Ignition timing Relationship Among Timing, Knock Correct Learn Value, and Knock Feedback Value Knock Retard Correction • The above described knocking magnitude judgment is performed, and based on the result, the ignition timing is retard-corrected using the advance/retard control • If a knocking judgment is given, the ignition timing is retarded by a specific amount The greater magnitude of knocking, the more the retarded amount (Reflected on all cylinders.) • If a knocking-free status lasts for a certain amount of time, the ignition timing is advance-corrected • By continuously performing the above corrections, the ignition timing is controlled at the knocking threshold point (for optimal ignition timing) • The control status of knock retard corrections can be checked by means of the “Knock Correct Learn Value” and the “Knock Feedback Value”, which can be monitored on Techstream Maximum Advance Value and Maximum Retard Value Technical Training • The maximum advance value and the maximum retard value are predetermined to prevent an extraordinary advance or retard of ignition timing as a result of individual advance corrections • The maximum advance value is targeted at an ignition timing that allows the best performance conceivable to be obtained from an engine (If advanced beyond it, knocking occurs, which leads to a decrease in engine output or fuel economy.) • The maximum retard value is targeted at a fool-proof ignition timing that is free of knocking but involves some compromise in engine performance (power and fuel consumption) 121 Hi-Tech Update - Advanced Engine Control Relationship Among Timing, Knock Correct Learn Value, and Knock Feedback Value Technical Training Technician Handbook The illustration above demonstrates ignition timing correction based on knock signal feedback 122 Hi-Tech Update - Advanced Engine Control Technician Handbook Conditions under which a Knocking Problem Occurs Technical Training 123 Technician Handbook Hi-Tech Update - Advanced Engine Control Logical steps to think Calculation What is the specific gravity of air? (at 15°C / 59°F The specific gravity of air at 0°C / 32°F is 1.293 kg/m3 The specific gravity of air at 15°C / 59°F can be derived by “Specific gravity of air at 0°C / 32°F × (273 / Temperature*).” Therefore, Specific gravity of air at 15°C / 59°F (kg/m3) = 1.293 × (273 / 288**) = 1.23 kg/m3 = 0.00123 g/cm3 * Absolute temperature K (0°C / 32°F = 273 K) ** 15°C / 59°F = 273 K + 15 K = 288 K What is the MAF per engine cycle? (1000 cc = 1000 cm3) The MAF per cycle (g) = Specific gravity of air × displacement = 0.00123 g/cm3 × 1000 cm3 = 1.23 g Number of cycles per second What is the MAF per second at 2000 rpm? MAF per second = 2000 rpm ÷ 60 sec ÷ = 16.7 cycles = MAF per cycle × Number of cycles per second = 1.23 g × 16.7 cycles = 20.5 g/sec Unit of MAF Technical Training 124 ... vehicle must driven to clear the permanent DTC Technical Training 11 Hi- Tech Update - Advanced Engine Control Technician Handbook Permanent DTC Technical Training 12 Hi- Tech Update - Advanced Engine. .. 125 Technical Training Hi- Tech Update - Advanced Engine Control Course 973A: Introduction to Advanced Engine Control Technical Training Technician Handbook The technician will be... Technical Training 14 Hi- Tech Update - Advanced Engine Control Permanent DTC Technical Training Technician Handbook Drive this pattern to clear permanent DTC after using scantool 15 Hi- Tech Update