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Multiport Fuel Injection






Wiring and Components, Checking with Test Box 105 Pin (V.A.G 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 105 Pin (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".

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".

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 the 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.

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) ] Service and Repair.

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

- Perform test as described in the relevant repair sequences.

Installing the ECM

Install in reverse order of removal.

- Thereafter, the ECM must be equipped with the protective housing.

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

- Always use new shear bolts.

The procedures to follow after connecting the new ECM are described in Guided Fault Finding and Guided Functions.

When ending Guided Fault Finding, the tester attempts to erase the Diagnostic Trouble Code (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.