Scan Tool Connecting

Wiring and Components, Checking using Test Box VAG 1598/42

Special tools, testers and auxiliary items required

• Adapter Cable (V.A.G 1598/39-1)

• Adapter Cable (V.A.G 1598/39-2)

• Test Box (V.A.G 1598/42)

• 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.





• 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.

• The (V.A.G 1598/42) is designed so that it can be connected simultaneously to the engine control module harness and the engine control module 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 engine control module is to remain connected to the test box or not.

- Install the protective body covers. Refer to => [ Protective Body Covers, Installing ] Procedures.

The respective engine control module must be removed to disconnect the connectors from it.

• Engine Control Module (J623), removing and installing, refer to => [ Engine Control Module ] Engine Control Module.

• Engine Control Module 2 (J624), removing and installing, refer to => [ Engine Control Module 2 ] Engine Control Module 2

CAUTION!
To avoid damaging electronic components, set measuring range before connecting test leads and observe all test requirements.

- Connect (V.A.G 1598/42) to wiring harness with (V.A.G 1598/39-1) or (V.A.G 1598/39-2). Clamp test box Ground (GND) clip to battery negative terminal. The procedure will indicate whether the engine control module is to be connected to the test box or not.





- Perform the test as described in the corresponding repair procedure.

Installing Engine Control Module

Install in reverse order of removal.

- A metal retainer must be installed on the engine control module.

- 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 DTC memory and erase if necessary. Vehicle diagnostic, testing, and information system (VAS 5051B)

• When ending guided fault finding, the tester attempts to erase the DTC memory of all control modules. If this is not successful, the remaining DTCs stored in memory must be corrected until all DTCs can be erased.