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2007-2017 JEEP COMPASS
2.4L I4•AWD•AUTOMATIC•gas
16 active safety recalls on this vehicle — view recalls
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Repairs0Labor495Torque3140Fluid10DTC1923Battery1Maintenance0Recalls16
C121Chigh severityChassis

Master Cylinder Pressure Sensor Circuit

on 2007-2017 Jeep Compass 2.4L I4 · AWD

What this code means

The brake master cylinder pressure sensor circuit is reading out of range. This affects brake pressure monitoring used by ABS and stability control.

Symptoms

  • ABS and ESP lights on
  • Brake warning message
  • Reduced brake assist

Common causes

  • Faulty pressure sensor
  • Damaged sensor wiring
  • Corroded connector
  • Faulty ABS module

Diagnostic steps

  1. Read pressure sensor data
  2. Inspect sensor connector
  3. Check circuit continuity
  4. Replace pressure sensor if faulty
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