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Home >> Audi >> 2005 >> A8 Quattro Sedan (4E2) V8-4.2L (BFM) >> Repair and Diagnosis >> Transmission and Drivetrain >> Automatic Transmission/Transaxle >> Control Module >> Testing and Inspection
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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.
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