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P0555high severityPowertrain

Brake Booster Pressure Sensor Circuit Range/Performance

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

The brake booster pressure sensor signal is outside the expected range. The reading does not match actual booster vacuum or pressure conditions.

Symptoms

  • Check engine light on
  • Hard brake pedal feel
  • Possible cruise control disable

Common causes

  • Faulty brake booster pressure sensor
  • Vacuum leak at booster
  • Damaged wiring or connector
  • Faulty PCM

Diagnostic steps

  1. Retrieve freeze frame data
  2. Check booster vacuum with a gauge
  3. Inspect sensor wiring and connector
  4. Replace pressure sensor if faulty

Other Powertrain codes on this vehicle

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