C0088moderate severityChassis
Brake Fluid Level Sensor Circuit
on 2001 Kia Optima 2.4L I4 · FWD
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
- Check brake fluid level first
- Inspect sensor connector
- Test sensor circuit continuity
- Add brake fluid and verify warning clears
- 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.
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