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Engine Control Module (ECM), Replacing




Engine Control Module, Replacing

The Engine Control Module (ECM) controls fuel injection, the throttle valve control module, oxygen sensor control, ignition, knock control, EVAP canister purge regulator valve, engine speed limitation via fuel injectors and fuel pump relay, camshaft adjustment and On Board Diagnostic (OBD)

If the Engine Control Module (ECM) is replaced on vehicles with automatic transmission, the kickdown shift point has to be relearned. Test kickdown shift point

Special tools and equipment
- V.A.G1551 Scan Tool with VAG1551/3 Adapter

Procedure
- Print out old control module identification, and thus also its coding, as follows:
- Connect V.A.G 1551 scan tool (VAG1552). Switch ignition on and select Engine Control Module (ECM) using address word 01 (connecting scan tool and selecting ECM).

V.A.G1551 Scan Tool display indicates control module identification, e.g.:


3B0907551G 2.8l V6/5V G AT D05 ->
Coding 07551 WSC 00000



- Press PRINT button of Scan Tool (ST) to print out control module identification.
- Press -> button.
- Press 0 and 6 for function "End Output", and then press Q to exit from input mode.

Indicated on display


Rapid data transfer HELP
Select function XX



- Switch ignition off.







- Remove cover of protective housing for control modules.







- Using a screwdriver, carefully pry off retaining bracket (arrow).
- Disengage connector from control module and disconnect.
- Remove old control module and insert new one.
- Check old coding and code new control module.
- Adapt new control module to throttle valve control module.
- In vehicles with cruise control: Check whether this function is activated. If "G" does not appear in control module identification, activate cruise control.
- Check DTC memory of new Engine Control Module (ECM), and erase anything that might be in it.
- Adapt new control module to immobilizer.
- Perform idle test.