C03xx OBD-II Codes (C0300–C0399)
100 fault codes in the C03xx range. Click any code for causes, diagnostic steps, severity, and common fixes.
C0300 critical
Electronic Parking Brake System Malfunction
C0301 critical
Electronic Parking Brake Motor Circuit
C0302 critical
Electronic Parking Brake Motor Circuit Open
C0303 critical
Electronic Parking Brake Motor Circuit Short
C0304 moderate
Electronic Parking Brake Switch Circuit
C0305 moderate
Electronic Parking Brake Switch Circuit Low
C0306 moderate
Electronic Parking Brake Switch Circuit High
C0307 moderate
Electronic Parking Brake Release Switch
C0308 moderate
Electronic Parking Brake Apply Switch
C0309 moderate
Electronic Parking Brake Position Sensor
C0310 critical
EPB Caliper Left Rear Malfunction
C0311 critical
EPB Caliper Right Rear Malfunction
C0312 critical
EPB Caliper Left Rear Circuit
C0313 critical
EPB Caliper Right Rear Circuit
C0314 critical
EPB Caliper Left Rear Stuck
C0315 critical
EPB Caliper Right Rear Stuck
C0316 moderate
EPB Cable Tension Sensor Circuit
C0317 moderate
EPB Cable Tension Sensor Range
C0318 moderate
EPB Cable Tension Too High
C0319 moderate
EPB Cable Tension Too Low
C0320 moderate
EPB Temperature Sensor Circuit
C0321 moderate
EPB Temperature Sensor Range
C0322 moderate
EPB Over-Temperature Condition
C0323 moderate
EPB Under-Temperature Operation
C0324 moderate
EPB Auto Apply Feature Malfunction
C0325 moderate
EPB Auto Release Feature Malfunction
C0326 moderate
EPB Hill Hold Feature Malfunction
C0327 moderate
EPB Hill Hold Sensor Circuit
C0328 moderate
EPB Hill Hold Sensor Range
C0329 moderate
EPB Hill Hold Performance
C0330 critical
EPB Control Module Communication
C0331 critical
EPB Control Module Internal
C0332 critical
EPB Control Module Power Supply
C0333 critical
EPB Control Module Ground Circuit
C0334 moderate
EPB Voltage Too Low
C0335 moderate
EPB Voltage Too High
C0336 moderate
EPB CAN Bus Communication Error
C0337 moderate
EPB Network Timeout
C0338 moderate
EPB Module Configuration Error
C0339 moderate
EPB Software Version Mismatch
C0340 moderate
Parking Brake Pedal Switch Circuit
C0341 moderate
Parking Brake Pedal Switch Low
C0342 moderate
Parking Brake Pedal Switch High
C0343 moderate
Parking Brake Cable Adjustment
C0344 moderate
Parking Brake Cable Broken Left
C0345 moderate
Parking Brake Cable Broken Right
C0346 critical
Parking Brake Drum Overheated
C0347 moderate
Parking Brake Drum Worn
C0348 moderate
Parking Brake Shoe Worn
C0349 moderate
Parking Brake Adjuster Stuck
C0350 moderate
Auto Hold System Malfunction
C0351 moderate
Auto Hold Brake Pressure Sensor
C0352 moderate
Auto Hold Activation Circuit
C0353 moderate
Auto Hold Release Circuit
C0354 moderate
Auto Hold Switch Circuit
C0355 moderate
Auto Hold Switch Circuit Low
C0356 moderate
Auto Hold Switch Circuit High
C0357 moderate
Auto Hold Hydraulic Control
C0358 moderate
Auto Hold Timeout Error
C0359 moderate
Auto Hold System Performance
C0360 low
Hill Start Assist System Malfunction
C0361 low
Hill Start Assist Pressure Sensor
C0362 low
Hill Start Assist Gradient Sensor
C0363 low
Hill Start Assist Gradient Sensor Circuit
C0364 low
Hill Start Assist Activation Error
C0365 low
Hill Start Assist Release Error
C0366 low
Hill Start Assist Timeout
C0367 low
Hill Start Assist Brake Pressure Low
C0368 low
Hill Start Assist Brake Pressure High
C0369 low
Hill Start Assist Performance
C0370 moderate
Brake Booster Vacuum Sensor Circuit
C0371 moderate
Brake Booster Vacuum Sensor Low
C0372 moderate
Brake Booster Vacuum Sensor High
C0373 moderate
Brake Booster Vacuum Sensor Range
C0374 critical
Electric Brake Booster Motor Circuit
C0375 critical
Electric Brake Booster Motor Open
C0376 critical
Electric Brake Booster Motor Short
C0377 critical
Electric Brake Booster Position Sensor
C0378 critical
Electric Brake Booster Performance
C0379 critical
Electric Brake Booster Malfunction
C0380 moderate
Brake Pedal Position Sensor A Circuit
C0381 moderate
Brake Pedal Position Sensor A Low
C0382 moderate
Brake Pedal Position Sensor A High
C0383 moderate
Brake Pedal Position Sensor A Range
C0384 moderate
Brake Pedal Position Sensor B Circuit
C0385 moderate
Brake Pedal Position Sensor B Low
C0386 moderate
Brake Pedal Position Sensor B High
C0387 moderate
Brake Pedal Position Sensor B Range
C0388 critical
Brake Pedal Position Sensor Correlation
C0389 moderate
Brake Pedal Position Sensor Performance
C0390 moderate
Brake Light Relay Circuit
C0391 moderate
Brake Light Relay Circuit Open
C0392 moderate
Brake Light Relay Circuit Short
C0393 moderate
Brake Light Relay Performance
C0394 moderate
Brake Proportioning Valve Circuit
C0395 moderate
Brake Proportioning Valve Stuck
C0396 moderate
Brake Proportioning Valve Performance
C0397 critical
Trailer Brake Control Module Communication
C0398 critical
Trailer Brake Output Circuit
C0399 critical
Trailer Brake System Performance