Operation CHARM: Car repair manuals for everyone.

Control Module: Testing and Inspection






Transmission Control Module Voltage Supply, Checking

Special tools, testers and auxiliary items required

Multimeter (VAG1526)





Test adapter kit (VAG1594A)





Test Prerequisite

Transmission electronics fuses OK

Ground (GND) connections on engine and transmission OK

Battery voltage at least 12.5 V

Alternator OK

Ignition switched off.

Test Sequence





CAUTION!
Only touch Mechatronic electrical connector after you have discharged electrostatically on a grounded object, e.g. skin contact with vehicle Ground (GND).

The terminals in the 16-pin connector - arrow - of the wiring harness from transmission housing to Mechatronic must not be touched with the hands under any circumstances. The control module and Mechatronic could be destroyed by static discharge.

No measuring instruments should be connected to the 16-pin connector of the wiring harness from transmission housing to Mechatronic.

- Touch vehicle Ground (GND) with your hand (without gloves) to discharge static.

- Disconnect electrical connector on transmission. To do this, turn plug counterclockwise - arrow -.





- Connect multimeter as follows to vehicle wiring harness 16-pin connector for voltage measurement.









Specification: approx. battery voltage

- Connect multimeter for voltage measurement as follows:









- Switch ignition on.

Specification: approx. battery voltage respectively

- Switch off ignition.

If specifications are not obtained:

- Check wire connections for open circuit according to wiring diagram.

Specification: Wiring resistance 1.5 max. 1.5 ohms

- Repair wire connection, if necessary.

Final Procedures

After repairs, the following work steps must be performed in the mentioned sequence:

1. Retrieve DTC memory "Mode 3: Check DTC memory",.

2. If necessary, delete DTC memory "Mode 4: Reset/erase diagnostic data",.

3. If DTC memory was erased, generate readiness code.

- End diagnosis and switch ignition off.