C0090moderate severityChassis
Brake Booster Pressure Sensor Circuit
on 2015 Kia Forte 1.8L I4 · FWD
What this code means
Malfunction in the brake booster vacuum or pressure sensor circuit.
Symptoms
- Brake warning light on
- Hard brake pedal
- Increased stopping distance
- Check Engine Light may also be on
Common causes
- Faulty brake booster pressure sensor
- Vacuum hose leak
- Wiring damage
- Brake booster vacuum pump failure on diesel/turbo vehicles
Diagnostic steps
- Test brake booster vacuum with gauge
- Check vacuum hose to booster
- Test pressure sensor signal
- Inspect wiring and connector
- Check engine vacuum source
Repair notes
Repair vacuum leak or replace pressure sensor. On diesel vehicles, check vacuum pump.
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