Engine Control Module: Service and Repair

1999 Volkswagen Golf (1J1) L4-2.0L (AEG)SECTION Service and Repair



Engine Control Module Replacement

Special tools and equipment
V.A.G1551 Scan Tool (ST) with VAG1551/3 adapter cable

Removing
- First print out control module identification and thereby previous control module coding as follows:
- Connect V.A.G1551 (VAG1552) Scan Tool (ST). Refer to "Scan Tool Testing/VAG1551/Functional Check" Testing and Inspection
- Switch ignition on and press buttons -0- and -1- to insert "Engine Electronics" address word 01.

Indicated on display: control module identification and coding


06A906018J MOTRONIC M5.9.2 HSV02 ->
Coding 00000 WSC 00000



- Print out control module identification by pressing scan tool PRINT button.
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06 and press -Q- button to confirm input.
- Turn off ignition.
- Remove wiper arms and plenum chamber cover.
- Release harness connector from control module and disconnect







- Press retaining tab (arrow) to left and remove control module.

Installing
- Place new control module into retaining frame.
- Install control module harness connector and lock.
- Check previous coding and coding of new control module. Refer to "Engine Control Module, Coding", Testing and Inspection
- Check DTC memory. If necessary, repair any malfunctions and erase DTC memory. Refer to "Displaying and Reading Trouble Codes/With Manufacturer Scan Tool/Check DTC Memory (Function 02)" Testing and Inspection
- Adapt new control module to throttle valve control module. Refer to "Engine Control Module to Throttle Valve Control Module, Adaptation", Testing and Inspection
- Check idle speed. Testing and Inspection
- Generate readiness code. Refer to "Monitors, Trips and/or Drive Cycle/Generating Readiness Code" Testing and Inspection
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.