Engine Control Unit Locked: Troubleshooting Guide

Hi there,

When I connected my VAG-COM to my Golf IV AHF for the first time today, the error message 'Engine control unit locked' appeared during the diagnostic scan. After clearing the error and restarting the engine several times, the error no longer reappeared. Does this error have any significant meaning (probably not), or is it related to the VAG-COM itself?

Greetings.
Jean.

Have you ever had any problems with your immobilizer system?
This usually happens when the immobilizer system prevents the car from starting because of an incorrect key, a mismatch between the engine control unit (ECU) and the immobilizer, or a malfunction/defect in the ECU.

If your car starts and runs normally, there's no need to worry.