C0086moderate severityChassis
Master Cylinder Pressure Sensor Circuit Low
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
Low voltage from the master cylinder brake pressure sensor, indicating a circuit fault.
Symptoms
- ABS light on
- Stability control disabled
- Brake assist may not function
- Regenerative braking malfunction on hybrids
Common causes
- Sensor short to ground
- Faulty pressure sensor
- Connector pin damage
- Low battery voltage to sensor
Diagnostic steps
- Test sensor supply voltage
- Check signal wire for shorts to ground
- Inspect sensor connector
- Test sensor output while pressing brake pedal
- Check for related ABS module codes
Repair notes
Replace master cylinder pressure sensor. Verify supply voltage.
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C0021
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C0026
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