Scan Tool Connecting

Wiring and Components, Checking with 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.

• If a wiring connection to the ECM is to be tested, use the wiring diagrams to determine through which connector the electrical wiring connection leads to the ECM. Lead the electrical wiring connector to the 60-pin connected, then connect the smaller of the two connectors (V.A.G 1598/39-1) to the input "A" on the Test Box (V.A.G 1598/42).

• If an electrical wiring connection leads to the 94-pin connector according to wiring diagram, connect the larger of the two connectors (V.A.G 1598/39-2) as follows. The connector designated with an "A" must be connected to input "A" of the Test Box (V.A.G 1598/42) and the connector "B" must be connected to input "B" of the Test Box (V.A.G 1598/42).

• The Test Box (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.

CAUTION!
To avoid damaging electronic components, switch to the corresponding measuring range and observe all test conditions before connecting the test leads.

- Remove Engine Control Module (ECM) (J623). Refer to => [ Engine Control Module ] Service and Repair.

- Connect the Test Box (V.A.G 1598/42) to the wiring harness connector. Connect the Ground clip on the test box to the battery ground. The procedures will indicate whether the Engine Control Module (ECM) (J623) is to be connected to the test box.

- Perform test as described in relevant repair sequences.

Installing the engine control module (ECM):

Install in reverse order of removal.

- Thereafter, the engine control module must be equipped with the metal retainer.

- New shear bolts must always be used.

- Clean the threaded holes of residue and locking compound for the new shear bolts. Cleaning can be performed with a thread cutter (tap).

- 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.