GMC OBD Codes: Meaning & Fixes

P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High P0420 Powertrain The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly. Low P0700 Powertrain The transmission computer found a fault and asked for the check engine light – read the TCM… Moderate P0128 Powertrain The engine takes too long to warm up, which almost always points to a thermostat stuck open. Low P2138 Powertrain The two sensors in the gas pedal report different pedal positions, so the PCM limits throttle… Moderate P0008 Powertrain Camshaft timing on bank 1 has drifted from the crankshaft. Often a stretched timing chain. Moderate

B0012 Body Airbag firing-loop fault; location depends on the make: passenger dash airbag or, on GM… High B0051 Body SAE: front middle seat buckle sensor fault. On GM vehicles: the airbag module has logged… High P0016 Powertrain The bank 1 intake cam and the crankshaft are out of step, most often from a stretched or jumped… High P0018 Powertrain The bank 2 intake cam is out of step with the crankshaft on a V or boxer engine; chain wear… High P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High P0756 Powertrain Solenoid B isn't moving fluid the way the TCM expects – the car may pull away in 3rd or 4th. High P0894 Powertrain The transmission computer measured slip inside the gearbox that shouldn't be there. Clutches… High