LEARNING GUIDE POWERTRAIN SPECIALIST VOLKSWAGEN POWERTRAIN CONTROL SYSTEMS DIAGNOSTICS ONE COURSE NUMBER: PT310-01
Notice Due to the wide range of vehicles makes and models, the information given during the class will be general in nature and should not be taken as specific to any vehicle/unit. Please consult manufacturer specifications for the correct number/specifications and repair procedures for the vehicle you are testing. This document is meant to be used as a guideline only. For further information, please contact: 1888 224 3834 No part of this book may be reproduced, stored in any retrieval system or transmitted in any form or by any means (including but not limited to electronic, mechanical, photocopying and recording) without prior written permission of CARS Network. This applies to all text, illustrations, tables and charts. Copyright 2010 CARS Network Page ii
Introduction OBJECTIVES Upon successful completion of this segment the participant will be able to: Interpret scan tool data from various inputs and output devices and understand the direct relationship to powertrain management and control. Locate and identify system components related to fault detection DTCs Describe the function, normal operation and symptoms of failure regarding system components. Perform diagnostic test procedures Discuss systems requiring reset, re-learn and re-programming procedures Expanded information and diagnostic s concerning: - MAF Sensor P0100-P0104 - Idle Speed Control P0505-P0511 - Secondary Air Injection P0410-P0419 - Intake Air Systems P1297-P1557 Page 1
Volkswagen Powertrain 1 Volkswagen has used been known to use many different types of fuel injection systems, even within the same year. The type of fuel injection system used depends on the model and engine type. Volkswagen Fuel Injection Applications 1985-2001 Year 1985 CIS (K- Jetronic) Cabriolet, Golf, Jetta & Quantum CIS-E (KE- Jetronic) Quantum 2.2L 5 Scirocco CIS-E Motronics Fuel Injection Type Digijet Digifant 1 (LH-Jetronic) Vanagon 1.9L 4 Digifant (L-Jetronics) Mono- Motronics Motronics 1986 1987 1988 1989 1990 1991 Cabriolet, Golf & Jetta 1.8L 4 Cabriolet & Golf 1.8 4 cyl GTI & Scirocco Quantum 2.2L 5 Fox, GTI, Jetta & Scirocco Quantum 2.2L 5 Cabriolet & Fox 1.8L 4 GTI, Jetta & Scirocco 1.8L DOHC 4 Quantum 2.2L 5 Cabriolet & Fox 1.8L 4 GTI & Jetta 1.8L DOHC 4 Fox 1.8L 4 GTI, Jetta & Passat 2.0L 4 DOHC GTI, Jetta & Passat 2.0L 4 DOHC Vanagon 2.1L 4 cyl Vanagon 2.1L 4 cyl Vanagon 2.1L 4 cyl CALIFORNIAN : Cabriolet, Fox Corrado, Golf, GTI & Jetta 1.8L 4 Vanagon 2.1L 4 Vanagon 2.1L 4 Vanagon 2.1L 4 cyl Golf & Jetta 1.8L 4 Golf & Jetta 1.8L 4 Cabriolet, Fox Corrado, Golf, GTI & Jetta FEDERAL: Cabriolet, Fox Corrado, Golf, GTI & Jetta Page 2
Year 1992 1993 1994 1995 1996 OBD CIS (K- Jetronic) CIS-E (KE- Jetronic) CIS-E Motronics GTI, Jetta & Passat 2.0L 4 DOHC Passat 2.0L 4 DOHC Digijet Digifant 1 (LH-Jetronic) Vanagon 2.1L 4 cyl CALIFORNIAN : Cabriolet, Fox Corrado, Golf, GTI & Jetta 1.8L 4 CALIFORNIAN : Cabriolet, Fox& Corrado Golf I & Jetta I 2.0L 4 Eurovan 2.5L 5 Digifant (L-Jetronics) FEDERAL: Cabriolet, Fox Corrado, Golf, GTI & Jetta FEDERAL: Cabriolet, Fox & Corrado, Golf I & Jetta I 2.0L 4 Eurovan 2.5L 5 Eurovan 2.5L 5 Mono- Motronics Canadian Golf & Jetta 1.8L 4 Cyl Canadian Golf & Jetta 1.8L 4 Cyl Canadian Golf & Jetta 1.8L 4 Cyl Canadian Golf & Jetta 1.8L 4 Cyl Motronics Corrado & Passat 2.8L V6 DOHC Corrado & Passat 2.8L V6 Corrado, Jetta I & Passat 2.8L V6 DOHC Golf I, Cabrio, Jetta I & Passat 2.0L 4 Passat 2.8L V6 DOHC Cabrio, Golf & Passat 1997 OBD 1998 OBD 1999 OBD Bettle (1998^), Cabrio, Golf, GTI, Jetta, Passat, Passat Syncro & Eurovan 2000 OBD 2001 OBD Page 3
Common engine applications and codes Volkswagen Engine Code Chart Engine Code GX MZ HT RD RV PF PL 9A Number 4 4 4 4 4 4 4 4 Of cylinders Displacement 1.8L 1.8L 1.8L 1.8L 1.8L 1.8L 1.8L 2.0L Fuel Gas Gas Gas Gas Gas Gas Gas Gas Horsepower 85 90 100 102 100 105 123 134 Injection Type CIS CIS-E CIS CIS-E CIS-E DIGIFANT I OR DIGIFANT CIS-E CIS-E MOTRONICS Features CANADA ONLY 16V 16V Engine Code ME MF 1V AAA ABA ACC AHU AAZ Number 4 4 4 V6 4 4 4 4 Of cylinders Displacement 1.6L 1.6L 1.6L 2.8L 2.0L 1.8L 1.9L 1.9L Fuel Diesel Diesel Diesel Gas Gas Gas Diesel Diesel Horsepower 52 68 59 172 115 90 90 75 Injection Type MONO- MOTRONICS DIESEL DIESEL DIESEL DIESEL DIESEL 1993-1995 M2.9 1993-1995 M2.9 1996 M5.9 1996 M5.9 Features TURBO ECO TURBO VR6 CANADA CANADA TDI NOTES : Page 4
Volkswagen Fuel Injection Systems Operation Overview CIS: Continuous Injection Systems Completely Mechanical Measures Air Volume & Injects a Proportional Amount of Fuel CIS-E Silver or aluminum colour fuel distributor. The CIS-E fuel injection system is an electronic/mechanical fuel injection system. The airflow sensor and fuel pressure controls fuel metering. Page 5
CIS-E Motronics Components and Control Unit Inputs Digijet Components Digijet Limited Use Modified Bosch Air Flow System Group Fire Injector Separate Cold System NOTES : Page 6
Digifant I 1- Fuel tank 2- Electric fuel pump 3- Fuel filter 4- ECU 5- Fuel Injector 6- Fuel distributor rail 7- Fuel pressure regulator 8- Intake manifold 9- Throttle switch 10- Hot-wire mass airflow sensor 11- Oxygen sensor 12- Coolant temp. sensor 13- Distributor 14- Idle speed actuator 15- Battery 16- Ignition switch NOTES : Page 7
Mono-Motronics Motronics 2.9 (OBD I, 1993-1995) Page 8
Sensors Engine Coolant Temperature Sensor Mounted in the engine block water jacket Reports the engine temperature to the ECU in a form of a resistance value The ECU will use this information to determine the quantity of fuel to be delivered to the engine. When the engine coolant temperature increases, the sensor resistance value decreases negative temperature resistor (NTC) Symptoms of failure may include: DTCs, poor fuel economy, etc. Typical ECT (2002 Jetta) Intake Air Temperature IAT Sensor The intake air temperature sensor sends continuous intake air temperature information to the ECU/ECM The intake air temperature sensor is a thermistor-type variable resistor (increase in temperature results in a decrease in resistance) This resistance change will correspond with a voltage drop within the ECU that equals intake air temperature Specifications are typically 100-7000 ohms, 0-100 C temperature (maximum 1.5Ω wiring resistance), but ALWAYS consult service information NOTES : Page 9
EGR Valve Purpose: reduce emissions Symptoms of failure may include: rough idle/stalling at low speeds, high emission levels The EGR system reduces the amount of oxides of nitrogen (NO x ) emissions being emitted from the engines exhaust by allowing a small amount of exhaust gases back into the combustion chamber. Typical VW EGR Valve EVAP Systems Leak Detection Pump (OBD Compliant Motronics Systems) The leak detection pump (LDP) automatically detects a leak within the evaporative emission system. When pre-determined conditions have been met, the ECM will activate the LDP, which will pump a small amount of ambient air pressure into the fuel tank and lines. At the same time, the ECM closes the evaporative canister condensate drain valve and the evaporative canister purge valve. Typical Leak Detection Pump The leak detection pump will run for a certain length of time or until a pre-determined pressure has bee attained within the fuel tank and lines. If the system does not hold the correct amount of pressure, a DTC or fault is stored in the ECM memory. Page 10
Secondary Air Injection (AIR) The system consists of Air pump Combination valves Solenoid Vacuum lines cause the valves to open and close PSB Case study: June 3, 2004 MIL ON with DTCs P1346 and P1340 DTCs may be the result of an elongated timing chain Check memory for DTCs which indicate this may be the underlying problem (Typical operation always consult service information) Blows air in behind the exhaust valves during cold start for 100 seconds maximum. The system only activates on cold starts (coolant temperature is between 5 and 33 C) Produces oxygen rich exhaust gas, causes afterburning and reduces duration of the catalyst heat up phase Activated by ECM via Secondary Air Injection pump relay and combination valve After each subsequent engine start the SAI system will switch on for 10 seconds during idle (up to max 96 C ECT) and is then monitored by the system the O 2 sensor must be active during this procedure Note: If tools are required to pull relays or control modules out of the relay plate, service information may direct you to disconnect the battery ground strap make sure you have radio codes before you do! MAF Sensors Measures air flow quantity (Typical quantity: 2.0-5.0 g/sec for a 2002 Jetta always consult service information!) Critical sensor Symptoms of failure may include stalling, rough idle, no start, etc. Page 11
Throttle Control (The automatic control module (certain models) also uses the TPS. On Motronics 5.9 the TPS is incorporated in the throttle actuator control module. WOT typical value: 84-88%, idle: 12-16% (2002 Jetta, ALWAYS consult service information) EPC Notes (1999-2005 Jetta): No mechanical link between accelerator pedal and throttle valve two sensors use CAN to communicate: signal is sent from accelerator pedal to ECM, ECM signals Throttle Drive which operates the throttle valve. Main input for the system is the Accelerator Pedal Position sensor, but does use many components such as warning lamps, throttle valve control module, etc. consult service information. Electric motor (called the throttle valve actuator ) in throttle valve control module operates the throttle valve no matter engine speed or load. If the accelerator is pressed halfway, the throttle will be opened halfway. ECM can operate throttle independently. Mechanical default position known as emergency running gap happens if malfunction is detected Possible problems may include: High resistance or open Binding Incorrect adaptation after repair such as ECM replacement Preliminary checks: Coolant temperature above 80 C Accelerator pedal adjusted correctly if applicable Throttle clean Battery voltage must be good (usually at least 11.5 volts) Power drains (lights, etc.) off Park brake on, AC off Ground ok Page 12
Throttle Cable Adjustment (ALWAYS consult service information, 1998-2005 1.8L 4cyl 5v Turbo (Passat) used in this example) Manual Transmission: Adjust accelerator pedal cable by swapping positioning clip at support bracket so that WOT position is reached on cable pulley of Throttle Valve Control Module. Automatic Transmission: (Needs DVOM) Adjust accelerator pedal cable by swapping positioning clip at support bracket so that WOT position is reached on cable pulley of Throttle Valve Control Module. Release accelerator pedal Disconnect harness from kickdown switch (consult service information) Connect DVOM to kick down switch Measure resistance at switch (should be infinite) Slowly move accelerator pedal to WOT Just before kickdown point resistance should drop to 0 ohms (slightly before the stop) Typical sensor location (2003 Jetta) NOTES : Page 13