OBD-II trouble codes

Ranked by how often the code appears in real NHTSA owner complaints - not alphabetically. P = powertrain, B = body, C = chassis, U = network.

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Browse by symptom

Rough idle / shaking Stalling Hard starting Hesitation / power loss Flashing check engine light Poor fuel economy Shifting problems Temperature / cooling ABS / dashboard lights

Codes whose typical symptoms include abs / dashboard lights - most serious first:

P0504Brake Switch A/B Correlation P0705Transmission Range Sensor A Circuit (PRNDL Input)U0073Control Module Communication Bus A Off U0100Lost Communication With ECM/PCM A U0101Lost Communication With TCM U0121Lost Communication With Anti-Lock Brake System (ABS) Control Module A U0126Lost Communication With Steering Angle Sensor Module U0140Lost Communication With Body Control Module C0020ABS Pump Motor Control C0035Right Front Wheel Speed Sensor Supply P0500Vehicle Speed Sensor A Circuit P0503Vehicle Speed Sensor A Circuit Intermittent/Erratic/High P0720Output Shaft Speed Sensor Circuit U0001High Speed CAN Communication Bus U0155Lost Communication With Instrument Panel Cluster (IPC) Control Module U0293Lost Communication With Hybrid/EV Powertrain Control Module U0401Invalid Data Received From ECM/PCM A U0402Invalid Data Received From TCM U0415Invalid Data Received From Anti-Lock Brake System (ABS) Control Module U0416Invalid Data Received From Vehicle Dynamics Control Module U0418Invalid Data Received From Brake System Control Module A