Back to 2003 BMW 525iT E39

2003 BMW 525IT E39

2.5L I6 M54 TouringRWDAUTOMATICgas
Repairs0Labor595Torque2406Fluid7DTC722Battery0Maintenance0Recalls0
C0088moderate severityChassis

Brake Fluid Level Sensor Circuit

on 2003 BMW 525iT E39 2.5L I6 M54 Touring · RWD

What this code means

Malfunction in the brake fluid level sensor circuit in the master cylinder reservoir.

Symptoms

  • Brake warning light on
  • Low brake fluid warning
  • ABS may be disabled
  • Stability control may be disabled

Common causes

  • Low brake fluid level
  • Faulty float sensor in reservoir
  • Wiring to sensor damaged
  • Sensor connector corroded

Diagnostic steps

  1. Check brake fluid level first
  2. Inspect sensor connector
  3. Test sensor circuit continuity
  4. Add brake fluid and verify warning clears
  5. Check for brake fluid leaks

Repair notes

Fill brake fluid to proper level. If fluid is low, inspect for leaks at calipers, hoses, and wheel cylinders. Replace sensor if faulty.

Other Chassis codes on this vehicle

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