An ABS / ESC / traction light on a GTI is almost always a wheel-speed sensor — cheap — before it's the expensive module.
Symptoms:
- ABS + ESC (and sometimes the handbrake light) on together, the speedo maybe dropping out.
- A stored wheel-speed-sensor code naming the corner on VCDS.
The fix:
- Read the code, replace the named wheel-speed sensor, and clean the reluctor/tone ring — rust on it mimics a bad sensor.
- If VCDS points at the ABS control module/pump itself (internal or comms fault), that's a module repair/replace + coding — a specialist job, not a guess.
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