ON BOARD DIAGNOSTICS
- The Engine Control Module (ECM) is equipped with On Board Diagnostics (OBD). Before repairs such as fault finding, check the Diagnostic Trouble Code (DTC) memory first. Also the vacuum hoses and connections must be checked (unmetered air).
- Fuel hoses in engine compartment must only be secured with spring-type clips. The use of clamp or screw type clips is not permissible.
- For the electric components to work properly, a voltage of at least 11.5 Volts is required.
- Do not use sealants containing silicone. Particles of silicone drawn into the engine, will not be burnt in the engine and damage the oxygen sensor.
- The vehicles have a crash fuel shut-off. It reduces the risk of fire in an accident because the fuel pump relay switches the fuel pump off.
- This setup also makes it easier to start the engine. When the driver-side door is opened, the fuel pump is activated for 2 seconds so that pressure builds in the fuel system, observe safety measures. Refer to «TEST AND MEASURING INSTRUMENTS DURING TEST DRIVE»(ref-496076-S22689614382012082100000) .
TEST AND MEASURING INSTRUMENTS DURING TEST DRIVE
If special testing equipment is required during road test, note the following
| WARNING | Distraction and testing equipment that is not secured properly can cause accidents. The passenger airbag could pose a risk if it deploys in a collision. Operating testing equipment while driving causes it to shift position. There is an increased risk of injury due to unsecured testing equipment. Always secure testers on the rear seat with a strap and have a second person on the rear seat operate them. |
WIRING AND COMPONENTS, CHECKING WITH TEST BOX 105 PIN V.A.G 1598/42
Special tools and workshop equipment required
- Adapter Cable V.A.G 1598/39-1
- Adapter Cable V.A.G 1598/39-2
- Test Box 105 Pin V.A.G 1598/42
- Connector Test Set V.A.G 1594 C
- Voltage Tester V.A.G 1527 B
- Portable Multimeter V.A.G 1526 C
Note. The test box has 105 terminals. The connection cable can be separated from the test box. This means that as new Engine Control Module (ECM) connectors are introduced in the future, only a new cable must be designed and no longer the entire test box. The smaller of the two connectors on the ECM is assigned with terminals 1 to 60. The larger of the two connectors is assigned with terminals 1 to 94. For testing at the 60-pin harness connection, the -V.A.G 1598/39-1- is connected to the test box with connector -A-. Components of the 60-pin harness connection, refer to appropriate SYSTEM WIRING DIAGRAM. For testing at the 94-pin harness connection, the -V.A.G 1598/39-2- is connected to the test box with connectors -A- and -B-. Components of the 94-pin harness connection, refer to appropriate SYSTEM WIRING DIAGRAM. The V.A.G 1598/42 is designed so that it can be connected simultaneously to the ECM harness and the ECM itself. This is advantageous because electronic engine control remains fully functional (for example measurement of signals with engine running) when the test box is attached. The procedures will indicate whether the ECM is to remain connected to the test box or not. Always use V.A.G 1594 C to connect measuring equipment (for example V.A.G 1527 B, V.A.G 1526 C, etc.)
| WARNING | To avoid damaging electronic components, switch to the corresponding measuring range and observe all test conditions before connecting the test leads. |
The ECM must be removed to disconnect the ECM multi-pin connectors. Refer to Engine Control Module -J623 .
Connect the V.A.G 1598/42 to the wiring harness connector. Attach the ground clip on the test box to the battery negative cable. The procedures will indicate whether the ECM is to be connected to the test box.
Perform test as described in relevant repair sequences.
Installing the ECM
Install in reverse order of removal.
Thereafter, the ECM must be equipped with the metal retainer.
Clean threaded holes for shear bolts of locking compound residue. Cleaning can be performed with a thread cutter (tap).
Always use new shear bolts.
Check the Diagnostic Trouble Code (DTC) memory and erase if necessary.