C0065high severityChassis
ABS Accumulator Pressure Low
on 2004 Audi TT 3.2L VR6 · AWD
What this code means
The ABS brake pressure accumulator has insufficient pressure to support ABS or traction control operations.
Symptoms
- ABS light on
- Brake pedal very firm
- Long pedal travel
- Traction control disabled
- Warning chime
Common causes
- Leaking accumulator
- Faulty ABS pump not building pressure
- Accumulator nitrogen charge depleted
- Internal hydraulic leak in modulator
Diagnostic steps
- Check accumulator pressure with scan tool
- Monitor pump run time and pressure build
- Inspect for external brake fluid leaks
- Test pump motor operation
- Check for hydraulic unit internal leaks
Repair notes
Replace accumulator or ABS hydraulic unit. Bleed system thoroughly.
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