C0121high severityChassis
Electronic Parking Brake Motor Overcurrent
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The EPB motor is drawing more current than the module can supply.
Symptoms
- EPB warning light
- Parking brake partially applied
- Grinding noise when EPB activates
- EPB applies slowly
Common causes
- EPB motor seized or binding
- Brake caliper seized
- EPB cable or mechanism corroded
- Motor brushes worn
Diagnostic steps
- Command EPB apply and release, monitor current draw
- Inspect rear brake calipers for binding
- Check EPB mechanism for corrosion
- Test motor current draw with ammeter
- Lubricate EPB mechanism if accessible
Repair notes
Replace EPB motor or caliper if mechanism is seized. Clean and lubricate if corrosion is the cause.
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