Workshop Manual (Group 23) EDC III TAD1240GE, TAD1241GEVE TAD1242GEVE, TWD1240VE 1 Contents Safety information................................................ 2 Introduction......................................................... 2 General information ............................................. 5 About the Service Manual ................................... 5 Spare parts ......................................................... 5 Certified engines ................................................. 5 Repair instructions............................................... 6 Our common responsibility.................................. 6 Tightening torques .............................................. 6 Torqueangle tightening ....................................... 7 Lock nuts............................................................ 7 Strength classes................................................. 7 Sealants ............................................................. 7 General ................................................................. 8 Location of engine plates .................................... 8 Tools..................................................................... 9 Special tools ....................................................... 9 Technical data ..................................................... 10 Design and operation.......................................... 12 System description EDC III................................ 12 Component description, sensors and monitors.. 14 Electronic Control unit (ECU) ............................ 16 Control Interface Unit (CIU) ............................... 16 Unit injectors ..................................................... 17 Generator .......................................................... 17 Starter motor ..................................................... 17 Component diagram and location ...................... 18 Limit values......................................................... 19 Limit values, control unit (ECU) TAD1240_42GEVE .......................................... 19 Limit values, control unit (ECU) TWD1240VE ...................................................... 20 Limphome values.............................................. 21 Repair instructions.............................................. 22 When working with EDC III................................. 22 Control unit (ECU), replacement........................ 23 Start with booster batteries................................ 24 Functionality check............................................. 25 PC diagnostics program..................................... 25 Fault detection .................................................... 26 Symptoms and possible causes ........................ 26 Diagnostic function.............................................. 27 The role of diagnostic function ........................... 27 Diagnostic function affects the engine ............... 27 Reading out error codes ..................................... 27 Erasing error codes............................................ 28 Error codes EDC III............................................ 29 Electronic fault detection.................................... 46 General .............................................................. 46 Functionality check of cables and connectors.... 46 Fault detection on cables and connectors .......... 47 Splicing electrical cable for cable glove.............. 48 Checkfault detection of components ................. 49 Electrical system................................................. 62 Important about the electrical system ................ 62 Electrical system, overview ............................... 63 Wiring diagram TAD1240_42GEVE.................. 66 Wiring diagram TWD1240VE............................. 67 Wiring diagram, Control Interface Unit (CIU) ..... 68 Wiring diagram, Control Interface Unit (CIU) _ Power pack........................................................ 69 Index .................................................................... 70 EDC III TAD1240GE, TAD1241GEVE, TAD1242GEVE, TWD1240VE 2 Group 23 EDC III Safety information Safety information Introduction This Service Manual contains descriptions and repair instructions for the Volvo Penta products or product versions listed in the table of contents. This manual should be used together with the Service Manual Technical data for the relevant engine. Be sure to use the correct service literature. Carefully read the safety information and General information and Repair instructions in the Service Manual before starting service work. Important The following special warning symbols are found in the Service Manual and on the engine. WARNING Warns for the risk of injury, damage to the product or property or that serious mal functions could arise if the instructions are not followed. IMPORTANT Used to draw attention to any thing that could cause injury or the malfunction of a product or property. NOTE:Used to draw attention to important information to facilitate work operations or handling. To provide an overview of the dangers of which you should always be aware and the precautionary measu res that should always be taken, we have listed them here. Make it impossible for the engine to start. Turn off the current by means of the main switch (or switches) and lock it (them) in the off position before starting service work. Affix a warning sign in the driver_s area. As a rule, all service work should be performed when the engine is switched off. However, some work, such as certain adjustments, requires the engine to be running. Approaching a running engine could be dangerous. Bear in mind that loosefitting clothes or long hair could get caught in rotating parts and cause serious injury. If work is performed near a running engine, an incautious movement or dropped tool could in the worst case lead to bodily harm. Be mindful of hot surfaces (exhaust pipes, the turbochar ger, charge air pipes, starter elements, etc.) and hot liquids in lines and hoses on an engine that is running or has just been stopped. Before star ting the engine, refit all guards and protective elements that were removed in the course of performing service work. Make sure that the warning andor information decals affixed to the product are always in plain sight. Replace any decals that have been dama ged or painted over. Never start the engine unless the air filter is fitted. The rotating impeller in the turbocharger could cause serious injuries. Foreign objects in the inlet line could also cause machinery damage. Never use starter spray or the like to help start the engine. It could cause an explosion in the intake manifold. Danger of injury. Start the engine in well ventilated areas only. If the engine is running in a confined space, ex haust gases and crankcase gases should be conducted away from the engine compartment or workshop area. Avoid opening the coolant filler cap when the engine is still hot. Steam or hot coolant could squirt out while the builtup pressure is lost. If necessary, open the filler cap slowly and relea se pressure in the cooling system. Be extremely careful if a cock, plug or coolant line must be removed while the engine is still hot. Steam or hot coolant could squirt out in an unexpected di rection. Hot oil can cause burns. Avoid getting hot oil on your skin. Make sure that the lubricating system is depressurized before starting any work on it. Never start or run the engine with the oil filler cap removed as oil under pressure could then escape. Stop the engine before doing any work on the cooling system. 3 Group 23 EDC III Safety information If other equipment connected to the engine changes its center of gravity, special lifting devi ces may be needed to obtain the right balance and ensure safe handling. Never perform any work on an engine that is suspended solely from a lifting device. Never work alone when heavy components are to be removed, even if a safe lifting device such as a lockable block and tackle is used. Even if a lifting device is used, two people are generally required; one to handle the lifting device and the other to make sure that the components go cle ar and are not damaged when lifting. Always ensure in advance that there is suffi cient space for dismantling to be done without risk of injury or material damage. WARNING Electrical system and fuel system components of Volvo Penta products are desig ned and manufactured to minimize the risk of explosion and fire. The engine must not be run in environments in which they will be surrounded by explosive media. Always use fuel recommended by Volvo Penta. See the Owner_s Manual. Use of a lower grade fuel could damage the engine. On a diesel engi ne, a poor grade of fuel could lead to overrev ving of the engine, causing risk of injury and da mage. Poor fuel can also give rise to higher maintenance costs. Bear in mind the following when cleaning with highpressure equipment: never direct the jet of water on seals, rubber hoses, electrical compo nents or the radiator. Always use protective goggles when performing work in which splinters, grinding sparks and splashes of acid or other chemicals could occur. The eyes are especially sensitive and an injury could result in loss of sight. Avoid getting oil on your skin. Prolonged or re curring contact with oil can damage the skin, re sulting in irritation, dehydration, eczema and other skin disorders. From a hygienic point of view, used oil is more harmful than fresh oil. Wear protective gloves and avoid clothes and rags ingrained with oil. Wash regularly, particu larly before mealtimes. Use skin lotion intended for this purpose to avoid dehydration and facili tate cleansing of the skin. Most chemicals intended for the product (such as engine and transmission oils, glycol, gasoline and diesel oil) or chemicals for workshop use (such as degreasers, paints and solvents) are injurious to health. Read the instructions on the package carefully. Always follow prescribed sa fety rules (such as the use of respirators, pro tective goggles, gloves, etc.). Make sure that other personnel are not unknowingly exposed to substances that are injurious to health such as through the air they breathe. Make provision for good ventilation. Deal with used and surplus chemicals in the prescribed manner. Exercise great care when detecting leaks in the fuel system and testing fuel nozzles. Wear pro tective goggles. The jets from a fuel nozzle are under very high pressure and have great pene trative power; the fuel can penetrate deep into body tissues and cause serious injury. Risk of blood poisoning. All fuels and many chemicals are flammable. Make sure that they cannot be ignited by an open flame or spark. Gasoline, certain dilutants and hydrogen from batteries, when mixed with air in the right proportions, are highly flammable and explosive. No smoking Provide for adequa te ventilation and take the necessary safety me asures prior to the start of welding or grinding work in the vicinity. Always keep a fire ext inguisher easily accessible at the workplace. Ensure that rags saturated with oil and fuel, used fuel and oil filters are kept in a safe place prior to their disposal. Under certain conditions, sponta neous combustion can occur in oilingrained rags. Used fuel and oil filters are environmentally hazar dous waste and, together with used lubricating oil, contaminated fuel, residual paint, solvents, deg reasers and residual detergents, should be taken to a suitable plant for destruction. Batteries should never be exposed to open fla mes or electric sparks. Never smoke near the bat teries. When the batteries are being charged, they give off hydrogen which, when mixed with air, forms oxyhydrogen gas. This gas is highly flam mable and very explosive. A spark, which can oc cur if the batteries are connected incorrectly, could cause a battery to explode, resulting in inju ry and damage. Do not disturb the connections when attempting to start (risk of sparks) and do not lean over any of the batteries. 4 Group 23 EDC III Safety information Never mistake the positive and negative poles for each other when installing the batteries. This could cause serious damage to the electrical equipment. Compare with the wiring diagram. Always wear protective goggles when charging and handling batteries. The battery electrolyte contains highly corrosive sulfuric acid. If it gets on your skin, wash the area with soap and plenty of water. If the electrolyte gets in your eyes, rinse them at once with plenty of cold wa ter and seek medical attention immediately. Stop the engine and cut off the current with the main switch (or switches) before starting work on the electrical system. The engine should be switched off when adjus ting the clutch. Use the lifting eyes mounted on the engine when lifting it. Always check that all lifting equipment is in good condition and that it has the right capacity for the job (engine weight plus transmission and extra equipment, if any). To ensure safe handling and avoid damaging components mounted on the top of the engine, it should be lifted using an adjustable lifting beam or one adapted to the engine. All chains or cables should run parallel to each other and as perpendi cular as possible to the top of the engine. © 2001 AB VOLVO PENTA We reserve the right to make modifications. Printed on environmentally friendly paper. 5 Group 23 EDC III General information General information About the Service Manual This Service Manual contains descriptions and repair instructions for the standard versions of the TAD1240GE, TAD1241GEVE, TA1242GEVE and TWD1240VE engines. The Service Manual may show work operations perfor med on any of the engines listed above. Consequently, the illustrations and photographs showing certain details may not be completely accurate in a number of cases. The repair methods, however, are essentially the same. The engine designation and number are given on the type plate (see _Technical data TAD1240GE, TAD1241GEVE, TAD1242GEVE and TWD1240VE_). The engine designation and number should always be quoted in all correspondence concerning any of the eng ines. The Service Manual is primarily produced for Volvo Penta_s service workshops and their qualified person nel. It is therefore assumed that persons using the manual have the necessary basic knowledge and can perform work of a mechanicalelectrical nature that oc curs in their profession. Volvo Penta is continuously developing its products and we therefore reserve the right to introduce chan ges and modifications. All the information in this ma nual is based on product data available up to the time of printing. Any vitally important changes to the pro duct or service methods that are introduced after that date are announced in the form of Service Bulletins. Spare parts Spare parts for the electrical and fuel systems are subject to different national safety requirements. Vol vo Penta Original Spare Parts meet these require ments. Any type of damage occurring as a result of using nonoriginal Volvo Penta spare parts for the pro duct in question will not be covered under the terms of the warranty as undertaken by Volvo Penta. Certified engines For engines certified for national and regional environ mental legislation, the manufacturer undertakes to en sure that the environmental requirements are fulfilled both in new engines and those already in use. The product must correspond to the specimen product that was approved for certification. For Volvo Penta as the manufacturer to be answerable for ensuring that engi nes in use meet the stipulated environmental require ments, the following requirements as regards service and spare parts must be fulfilled: The service intervals and maintenance measures recommended by Volvo Penta must be followed. Only Volvo Penta Original Spare Parts intended for the certified engine version may be used. Service involving injection pumps, pump settings or unit injectors must always be performed by an authorized Volvo Penta workshop. The engine must not be rebuilt or modified in any way, except with accessories and service kits that Volvo Penta has developed for the engine in question. Installation changes to exhaust pipes and supply air ducts for the engine compartment (ventilation ducts) must not be made indiscriminately as this could affect exhaust emissions. Any security seals must not be broken by nonauthorized personnel. IMPORTANT When spare parts are required, use only Volvo Penta Original Spare Parts. If nonoriginal spare parts are used, AB Vol vo Penta will no longer be responsible for ensuring that the engine corresponds to the certified version. Any injury, damage or cost arising due to the use of nonoriginal spare parts for the product in question will not be covered under the terms of warranty as undertaken by Volvo Penta. 6 Group 23 EDC III Repair instructions Repair instructions The work methods described in the Service Manual apply to a workshop environment. The engine is there fore lifted out of place and mounted on an engine stand. Unless otherwise stated, reconditioning work that does not require the engine to be removed can be performed in situ using the same work methods. See the _Safety information_ chapter for a closer ex planation of the warning symbols found in the Service Manual. WARNING IMPORTANT NOTE: are by no means all embracing as we cannot of cour se foresee everything that could happen as service work is performed under the most widely varying con ditions. So we can only point out the risks we feel could arise as a result of incorrect handling when wor king in a wellequipped workshop using methods and tools that have been tested by us. All work operations for which there are Volvo Penta special tools are described in the Service Manual using these tools. Special tools have been developed to ensure as safe and efficient methods of working as possible. It is therefore the obligation of anyone using tools or work methods other than those recommended by us to ensure that there is no risk of injury or materi al damage and that such use does not result in mal function. In a number of cases, there may be special safety ru les and user instructions for the tools and chemicals mentioned in the Service Manual. Such rules and ins tructions must always be followed and there are no special instructions for them in the Service Manual. The majority of risks can be avoided by taking certain elementary precautions and using common sense. A clean workplace and a clean engine eliminate many risks of injury and faulty operation. It is extremely important, especially in connection to work on fuel systems, lubrication systems, inlet sys tems, turbochargers, bearings and seals, to keep out dirt and foreign particles of other kinds. If this is not done, malfunction or a shorter repair life could be the result. Our common responsibility Every engine consists of numerous interacting sys tems and components. The deviation of a component from its technical specification could dramatically in crease the environmental impact of an otherwise good engine. It is therefore extremely important for speci fied wear tolerances to be maintained, for systems with facilities for adjustment to be correctly set and for Volvo Penta Original engine spare parts to be used. The intervals in the engine maintenance schedule must be followed. Certain systems, such as fuel system components, may require special competence and special testing equipment. For environmental and other reasons, cer tain components are sealed at the factory. Work on these components must not be performed by persons not authorized for such work. Bear in mind that the majority of chemical products, if incorrectly used, are hazardous to the environment. Volvo Penta recommends the use of biologically de gradable degreasers for all cleaning of engine compo nents unless otherwise expressly stated in the Servi ce Manual. Take care to ensure that oils and residual detergent, etc. are dispatched for destruction and do not inadvertently end up in the environment. Tightening torques Tightening torques for vital bolted joints that should be tightened using a torque wrench are listed in _Techni cal Data: Tightening torques_ and are also given in the Service Manual_s work descriptions. All tightening tor ques refer to cleaned threads, bolt heads and contact surfaces as well as lightly oiled or dry threads. If lubri cants, thread locking compounds or sealants are re quired for bolted joints, the type concerned is stated in the work description and in _Tightening torques_. The general tightening torques in the table below are appli cable to bolted joints for which no special tightening torque is specified. The tightening torque is a guiding value and the joint need not in such case be tightened using a torque wrench. Size Tightening torque Nm lbf.ft. M5 6 4.4 M6 10 7.4 M8 25 18.4 M10 50 36.9 M12 80 59.0 M14 140 103.3 7 Group 23 EDC III Repair instructions Torqueangle tightening In torqueangle tightening, the bolted joint is tightened to a specified torque and then additionally tightened through a predetermined angle. Example: at 90° angle tightening the joint is tightened an additional 14 turn after the specified tightening torque has been reached, all in the same operation. Lock nuts Lock nuts that have been removed must not be reu sed. New ones must be fitted instead as the locking characteristics of the old nuts deteriorate or are lost if used several times. For lock nuts with a plastic insert, e.g. Nylock®, the tightening torques in the table should be reduced if the Nylock® nut has the same height or thickness as a standard allmetallic hex nut. Reduce the tightening torque by 25% for 0,32__ or larger bolt si zes. For higher or thicker Nylock® nuts, where the all metallic thread is as high as that of a standard hex nut, the tightening torques in the table are applicable. Strength classes Nuts and bolts are divided into different strength clas ses; the strength class is marked on the bolt head. A higher number indicates a stronger material. For ex ample, a bolt marked 109 is stronger than one mar ked 88. When undoing bolted joints, it is therefore im portant to make sure that the bolts are refitted in their original places. When fitting new bolts, check the spa re parts catalogue to ensure that the correct type is used. Sealants Several different types of sealants and locking fluids are used on the engine. Their properties differ and they are intended for joints of different strengths, tem perature ranges, resistance to oil and other chemicals, and for the various materials and clearances in the engine. For service work to be fully satisfactory it is important that the right types of sealants and locking fluids are used on the joints where such are required. In the appropriate sections of the Service Manual, we have indicated the agents used in the production of our engines. Similar agents or agents with corresponding properties but from a different manufacturer should be used in connection with service work. When using sealing agents and locking fluids, it is im portant for the surfaces concerned to be dry and free from oil, grease, paint, rust inhibitor and residue from old sealant. Always follow the directions of the manu facturer regarding temperature, hardening time and other instructions relating to the product. Two different basic types of agent are used on the engine. These are characterized by: 1. RTV agent (Room Temperature Vulcanizing). Used mostly on gaskets, e.g. sealing gasket joints or coa ted on gaskets. RTV agent is perfectly visible when the component has been dismantled and old RTV agent must be removed before the joint is sealed afresh. The following agents are of RTV type: Loctite® 574, Volvo Penta 8408791, Permatex® No. 3, Volvo Penta 11610995, Permatex® No. 77. In all cases, old sea lant can be removed with denatured alcohol. 2. Anaerobic agents. These harden in the absence of air. They are used when two solid parts like cast com ponents are fitted together without a gasket. They are also commonly used to secure and seal plugs, the th reads of studs, cocks, oil pressure monitors, etc. Hardened anaerobic agents are glasslike; they are therefore colored to make them more visible. Harde ned anaerobic agents are highly resistant to solvents and old agent cannot be removed. When refitting a component, thorough degreasing is required followed by application of fresh sealant. The following agents are anaerobic: Loctite® 572 (white), Loctite® 241 (blue). Note Loctite® is a registered trademark of the Loctite Corporation; Permatex® is a registered trademark of the Permatex Corporation. 8 Group 23 EDC III General The above plate shows: (K) Engine family (J) Swept volume (A) Engine designation (F1)Valve clearance, inlet (F2)Valve clearance, outlet (I) Emission Control devices (P) Only constant RPM (E) Part number _ decal (B) Engine code (in engine family) (C) OutputRPM (D) Fuel quantity (M) Engine speed (H) Certification approval number (EU) Explanation of engine designation: Ex. TAD1240GETWD1240VE T _ Turbo A _ Airtoair Charge air cooler W _ Water to air, intercooler D _ Diesel engine 12 _ Swept volume, liter 4 _ Generation 0 _ Version G _ Gen Set engine V _ Stationary and mobile operation E _ Emissions check Location of engine plates The plate below shows: 1 Engine designation 2 Serial number 3 Specification number General The plate below shows: 1 Engine designation 2 Specification number 3 Serial number (last six digits) engine block The plate below shows: A Engine designation B Net engine output (without fan) C Max. rpm D Computer kit number E Product number 9 Group 23 EDC III Tools Tools Special tools Tool Name use 874427 Tcoupling, diagnostic 885337 Cable, PC diagnostics program 951 2636 Pin tool, connector 999 8482 Gauge, connector 999 8505 36pin adapter, diagnostics 999 8534 4pin adapter, diagnostics 874427 885337 951 2636 999 8482 999 8505 999 8534 999 9324 Cable shoe pliers, repair 951 0060 Multimeter, fault detectioncheck 774 1383 CD, parameter setting tool 999 9324 951 0060 774 1383 The following special tools are used when working with the engine. Special tools can be ordered from AB Volvo Penta using the given number. 10 Group 23 EDC III Technical data Technical data Control unit Voltage ..................................................................24 V Connector ..............................................................2 x 36pin Water monitor, fuel prefilter Voltage ..................................................................24 V Connector ..............................................................3pin Contact type ..........................................................Closed in the presence of water Monitor, fuel pressure Voltage ..................................................................24 V Connector ..............................................................2pin Work area pressure:..............................................0_217,5 psi (0_15 BAR) Contact type ..........................................................Closed upon low fuel pressure Camshaft sensorflywheel sensor Inductive sensor Connector....................................2pin Combined sensor, oil pressuretemperature Voltage ..................................................................5 V Connector ..............................................................4pin Work area pressure:..............................................0_101,5 psi (0_7 BAR) Pressure signal .....................................................0.5_4.5 V Work area temperature:..........................................40°C 40°F to +140°C 284°F Type ......................................................................NTC (Negativ Terminal Coefficient) Combined sensor, charge air pressuretemperature Voltage ..................................................................5 V Connector ..............................................................4pin Work area pressure:..............................................5,8_58 psi (0,4_4 BAR) Pressure signal ......................................................0.5_4.5 V Work area temperature:..........................................40°C 40°F to +125°C 257°F Type ......................................................................NTC (Negativ Terminal Coefficient) Decreased Resistance with increased temp. 11 Group 23 EDC III Technical data Sensor, coolant temperature Voltage ..................................................................5 V Connector ..............................................................2pin Work area temperature:..........................................40°C 40°F to +150°C 302°F Type ......................................................................NTC (Negativ Terminal Coefficient) Monitor, coolant level Connected to ground. The switch is closed when the coolant level is loo low Connector ..............................................................2pin Contact type ..........................................................Closed when coolant level is low Unit injector Voltage ..................................................................90 V Connection.............................................................2 poles Injection pressure...................................................26100 psi Generator Voltage ..................................................................24 V Connection.............................................................2 poles Capacity ................................................................60 A Starter motor Voltage ..................................................................24 V Connection.............................................................2 poles Capacity ................................................................6 KW Decreased Resistance with increased temp. 12 Group 23 EDC III Design and operation Control module The EDC III system processor is located in the con trol module, protected from moisture and vibrations. The processor continually receives information regar ding: Engine speed Charge air pressure Charge air temperature Coolant temperature Oil pressure Oil temperature Fuel alarm, combined alarm for _water in fuel_ and _fuel pressure_ Coolant level This information is used to make exact determinations on current operating conditions and allows the proces sor to calculate the correct amount of fuel, check the condition of the engine, etc. Fuel management The engine_s fuel need is analyzed up to 100 times per second (depending on engine speed). The quantity and timing of fuel injection into the engine are control led completely electronically via fuel valves on the unit injectors. This means that the engine always receives the cor rect amount of fuel under all operating conditions, providing benefits including improved fuel economy and minimized exhaust emissions. The control module checks and controls the unit injec tors so that the correct amount of fuel is injected into each cylinder. It calculates and sets the injection ang le. This control is done primarily with the help of the tachometer sensors and the combined sensor for charge air pressuretemperature. The control module actuates the unit injectors via an electronic signal to the unit injectors_ electromagneti cally controlled fuel valve, which can then be opened or closed. When the fuel valve is open, fuel streams by, through the unit injector holes and out through the fuel chan nel. Fuel is not injected into the cylinder at this stage. When the fuel valve is closed, pressure is built up by the mechanically driven pump piston of the unit injec tor. Once enough pressure is built up, fuel is injected into the cylinder via the injector portion. The fuel valve is reopened and pressure in the unit in jector sinks while fuel injection to the cylinder ceases. To determine when the fuel valve should be opened or closed, the control module has access to signals from sensors and switches. System description EDC III EDC III, _Electronic Diesel Control_, is an electronic system with CAN communication for diesel engine manage ment. The system is developed by Volvo Penta and covers fuel management, diagnostic function, etc. The sys tem consists of a control module, six unit injectors, a number of sensors that provide information to the control module, and a data link connector for diagnostics and functionality checks. The EDC III system also has a _stand alone_ interface that can be linked directly to the engine control module on the engine. The engine can be linked to a _CAN_ interface and a _Control Interface Unit_ (CIU), which is an interface to the operator area. Design and operation 13 Group 23 EDC III Design and operation Calculation of fuel quantity The amount of fuel injected into a cylinder is calcula ted by the control module. The calculation gives the amount of time the fuel valve is closed (as fuel is in jected into the cylinder when the fuel valve is closed). The parameters that determine the amount of fuel in jected are: Requested RPM Engine protection functions Temperature Charge air pressure Cylinder balance When idling, the control module can provide the cylin ders with different amounts of fuel. This makes the engine idle more evenly. At higher RPM, all cylinders receive an equal amount of fuel. Diagnostic function The EDC III system has an internal diagnostic func tion that makes it possible to detect faults in the engi ne and sensor. The role of the diagnostic function is to detect and lo calize disruptions in the EDC III system, protect the engine and ensure that the machine remains in wor king order during serious disturbances. If a disturbance arises, the diagnostic indicator on the indicator panel begins blinking. When the diagnosis button is pressed, an error code is given as guidance for any fault detection. The diagnostic function can be read out via the display using the PC diagnostics pro gram. Idle adjustment (low idle) Idle can be adjusted to a value between 600 and 1200 RPM. 14 Group 23 EDC III Design and operation Component description Tachometer sensor, camshaft (2) The tachometer sensor is located on the upper timing cover. The tachometer sensor, which is linked to the camshaft, is an inductive sensor. It reads a toothed wheel with seven pins. The impulses from the cams haft sensor provide the control module information on which cylinder is next in line for injection and when it receives it. Oil pressuretemperature sensor (10) Oil pressure and oil temperature are measured by a combined sensor that is located on the lefthand side of the engine, next to the control module. The sensor is mounted in the engine block so that measurement is taken from the oil system_s main channel. The sensor consists of a nonlinear resistor whose resistance is dependant on the temperature of the resistor body. Resistance decreases as tempera ture increases. The pressure signal is a voltage signal proportional to the pressure. The reference voltage for the sensor is 5 Volts. The digits after the headings refer to _Component dia gram and location_. Water monitor, fuel prefilter (19) The monitor is located on the bottom of the fuel pre filter. Its role is to guard against water in the fuel system. The monitor consists of two copper pins between which resistance is measured. When resistance falls below the limit value, which indicates that there is wa ter in the fuel, a warning signal is sent to the control module. 15 Group 23 EDC III Design and operation Coolant temperature sensor (15) The sensor is located on the lefthand rear portion of the cylinder head. The sensor reads the temperature of the engine coo lant and sends the information to the control module. It consists of a nonlinear resistor whose resistance depends on the temperature of the resistor body. Re sistance decreases as temperature increases. Charge air pressuretemperature sensor (6) Charge air pressure and charge air temperature are measured with a combined sensor located on the inta ke manifold. The charge air pressure sensor measures absolute pressure, which is the sum of the charge air pressure and atmospheric pressure. The sensor sends a signal to the control module in the form of voltage that is pro portional to the absolute pressure. The sensor receives a reference voltage of 5 Volts from the control module. The charge air temperature sensor consists of a non linear resistor whose resistance depends on the tem perature of the resistor body. Resistance decreases as temperature increases. Tachometer sensor, flywheel (18) This sensor is located on the lefthand side of the fly wheel housing. The tachometer sensor on the flywheel is an inductive sensor. It reads the crankshaft position and engine speed using grooves in the flywheel. The signal is sent to the control module, which calculates the injec tion angle and amount of fuel. Fuel pressure monitor (12) The monitor is located on the lefthand side of the engine, mounted in the fuel filter bracket. Its task is to detect if the fuel pressure falls below 29 psi (2 BAR). The monitor is set to shut off when pressure falls below 29 psi (2 BAR). 16 Group 23 EDC III Design and operation Electronic Control Unit (ECU) (11) The control module (EMS) checks and controls the unit injectors so that the correct amount of fuel is in jected into each cylinder. It calculates and sets the in jection angle. This control is done primarily with the help of the tachometer sensors and the combined sensor for charge air pressuretemperature. The EDC III system processor is located in the con trol unit, protected from moisture and vibrations. The processor continually receives information regar ding: engine speed charge air pressure charge air temperature coolant temperature oil pressure oil temperature fuel alarm, combined alarm for _water in fuel_ and _fuel pressure_ coolant level This information is used to make exact determinations on current operating conditions and allows the proces sor to calculate the correct amount of fuel, check the condition of the engine, etc. Coolant level monitor (1) This monitor is located in the expansion tank. Its task is to detect if the coolant level in the cooling system (expansion tank) is too low. The monitor con sists of a contact that can be actuated magnetically. A hull located around the monitor actuates the contact differently depending on the coolant level. An alarm signal is sent if the coolant level is too low. Control Interface Unit (CIU) The CIU is a control unit that handles all interaction with the operator. It communicates with the engine over two serial com munication buses. J1939 is used for controlling and monitoring the engine. J1587 is used for diagnostics and backup. The CIU loads a number of switches and speed re quests and forwards them to the engine. It also con trols four analogue instruments and up to nine warning lamps. Using a diagnosis button and diagnostic lamp, the operator can read out error codes from the system. 17 Group 23 EDC III Design and operation Unit injectors (20) The unit injectors are located under the valve cover, mounted in the cylinder head. The engine_s fuel need is analyzed up to 100 times per second (depending on engine speed). The quantity and timing of fuel injection into the engine are control led completely electronically via the unit injectors_ electromagnetically operated fuel valves. This means that the engine always receives the correct amount of fuel under all operating conditions, providing benefits including improved fuel economy and minimized ex haust emissions. Generator (8) The beltdriven generator is located on the lefthand front edge of the engine. The voltage regulator of the generator is equipped with a sensor system. The sensor system compares the charging voltage between the generator connections, B+ and B, with the actual voltage between the positi ve and negative poles of the batteries. The voltage re gulator then compensates for any voltage drop in the lines between the generator and the battery by increa sing the charging voltage from the generator as needed. Starter motor (16) The starter motor is mounted on the flywheel housing on the righthand side of the engine. When the motor is cut in, a gear on the armature shaft of the starter motor is moved along the axis so that it meshes with the gear ring of the engine_s flywheel. The actuator solenoid of the starter motor controls both the axial movement of the gear and connection of the starter motor. In turn, the actuator solenoid of the starter motor is cut in via the start relay, which is activated when the ignition key is turned to position III or the start button is depressed. The starter motor relay (1) is mounted next to the star ter motor solenoid. 1 18 Group 23 EDC III Design and operation Component diagram and location 6 4 5 1 2 9 11 12 8 16 19 3 10 18 7 15 13 14 17 1. Coolant level monitor 2. Tachometer sensor, camshaft 3. Connection, diagnostic tool 4. Programming plug 5. Charge air pressuretemperature sensor 6. Extra stop 7. Main relay 8. Generator 9. Fuse 10A 10. Oil pressuretemperature sensor 11. Control unit (ECU) 12. Fuel pressure monitor 13. 8_pin connection (Data bus) 14. 23_pin connection (Stand alone) 15. Coolant temperature sensor 16. Starter motor 17. Starter motor relay 18. Tachometer sensor, flywheel 19. Water monitor, fuel filter 20. Unit injectors (one per cylinder) 20 Inside the Cover 19 Group 23 EDC III Limit values Limit values Limit values, electronic control unit (ECU) TAD1240GE, TAD124142GEVE Alarm values The maximum permissible values for charge air and coolant temperatures, for example, can be adjusted with the parameter setting tool and can thus vary within alarm limits. If the alarm values are exceeded, the system reduces the amount of fuel until the value is once again within the permissible interval. This function is a customer parameter that can be completely disengaged. Alarm limits TAD1240_42GE: Coolant temperature: Alarm lamp lights Engine is switched off Engine output 50% Standard value Volvo Penta 98°C 208°F 100°C 212°F Parameter setting (can be set by the customer) 95_101°C 203214°F +2°C 36°F over the alarm value NOTE: Engine protection can be switched off. Coolant level: Alarm lamp lights when the contact is activated and the engine is switched off Alarm switch is activated NOTE: Engine protection can be switched off. Charge air temperature: Standard value Volvo Penta 83°C 181°F 85°C 185°F NOTE: Engine protection can be switched off. Oil pressure: Standard value Volvo Penta Idle: 0.7 bar (10,2 psi) For oil pressure 0.3 bar (4,4 psi) lower than alarm value >1500 RPM: 2.5 bar For oil pressure 0.3 bar (4,4 psi) (36,3 psi) lower than alarm value NOTE: Engine protection can be switched off. Oil temperature: Standard value Volvo Penta 125°C 257°F 127°C 261°F Parameter setting (can be set by customer) 120_130°C 248266°F+2°C 36°F over alarm value NOTE: Engine protection can be switched off. Fuel pressure: Standard value Volvo Penta