GMC Fault Codes
On this page you can find the meaning of the fault code you may be seeing coming from your GMC.
Either choose your model from below or scroll down even further to search and see popular fault codes across all GMCs.
(click your model)
Search GMC Codes
Do you know the fault code already? Enter it in the box below and hit "Search Codes".
Popular GMC Fault Codes
These are the most popular GMC fault codes that people are searching for.
Evaporative Emission System High Purge FlowLearn More Fixes
Transmission Control System MalfunctionLearn More Fixes
Catalyst System Efficiency Below Threshold (Bank 1)Learn More Fixes
Transmission Component Slipping/ Transmission Mechanical Transfer Case 4x4 Switch Circuit FailureLearn More
Random/Multiple Cylinder Misfire DetectedLearn More Fixes
SCR NOx Catalyst Efficiency Below ThresholdLearn More
Evaporative Emission Control System Vent Control Circuit MalfunctionLearn More Fixes
Throttle/Pedal Position Sensor/Switch A / B Voltage CorrelationLearn More Fixes
Exhaust Camshaft Position Timing - Over-Advanced (Bank 1)Learn More Fixes
Intake Camshaft Position Timing - Over-Advanced (Bank 1)Learn More Fixes
Post Catalyst Fuel Trim System Too Rich Bank 2Learn More Fixes
IMRC Input Error (Bank 1)Learn More
Engine Position System Performance - Bank 1Learn More
Cylinder 5 Misfire DetectedLearn More Fixes
EBCM Motor Relay Circuit Low When On (Chevrolet)Learn More
Evaporative Emission Control System Leak DetectedLearn More Fixes
System Too Lean (Bank 1)Learn More Fixes
Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temperature)Learn More Fixes
Evaporative Emission Control System Purge Control Valve circuit MalfunctionLearn More
Evaporative Emission Control System Vent Valve/Solenoid Circuit MalfunctionLearn More Fixes
Intake Camshaft Position Actuator Circuit / Open (Bank 1)Learn More Fixes
Exhaust Camshaft Position Actuator Circuit / Open (Bank 1)Learn More Fixes
Crankshaft Position Camshaft Position Correlation Bank 1 Sensor BLearn More Fixes
Lost Communication with TCMLearn More
Lost Communication With Body Control ModuleLearn More
SCP (J1850) Invalid or Missing Data for Primary IdLearn More
Control Module Communication Bus "A" OffLearn More Fixes
Lost Communication With Fuel Pump Control ModuleLearn More
Lost Communication With ECM/PCM "A"Learn More Fixes
A/T FI Signal A High InputLearn More
SGC (Cam Position) Sensor Circuit Malfunction/ Crankshaft Position - Camshaft Position CorrelationLearn More
HO2S Insufficient Switching Sensor 1Learn More
Cam Control FaultLearn More
Intake Camshaft Position Timing - Over-Retarded (Bank 1)Learn More Fixes
Crankshaft Position Camshaft Position Correlation Bank 1 Sensor ALearn More Fixes
Heated Oxygen Sensor (HO2S) Heater Control Circuit Bank 1 Sensor 2Learn More Fixes
Mass or Volume Air Flow Circuit Low Voltage InputLearn More Fixes
Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance ProblemLearn More Fixes
Intake Air Temperature Circuit High InputLearn More Fixes
O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)Learn More Fixes
O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)Learn More Fixes
O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)Learn More Fixes
O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)Learn More Fixes
O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)Learn More Fixes
O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)Learn More Fixes
System Too Rich (Bank 1)Learn More Fixes
System Too Rich (Bank 2)Learn More Fixes
Cylinder 1 Misfire DetectedLearn More Fixes
Cylinder 2 Misfire DetectedLearn More Fixes
Cylinder 3 Misfire DetectedLearn More Fixes
Cylinder 4 Misfire DetectedLearn More Fixes
Cylinder 6 Misfire DetectedLearn More Fixes
Knock Sensor 1 Circuit (Bank 2 or Single Sensor)Learn More Fixes
Knock Sensor 2 Circuit Low Input (Bank 2)Learn More Fixes
Crankshaft Position Sensor A Circuit MalfunctionLearn More Fixes
Camshaft Position Sensor Circuit Range/PerformanceLearn More Fixes
Exhaust Gas Recirculation Flow Insufficient DetectedLearn More Fixes
Catalyst System Efficiency Below Threshold (Bank 2)Learn More Fixes
Evaporative Emission Control System Incorrect Purge flowLearn More Fixes
System Gross Leak Evaporative EmissionLearn More Fixes
Evaporative Emissions System Small Leak DetectedLearn More Fixes
Fuel Level Sensor Circuit High InputLearn More Fixes
Idle Control System RPM higher Than ExpectedLearn More Fixes
Post Catalyst Fuel Trim System Too Lean Bank 1Learn More Fixes
Post Catalyst Fuel Trim System Too Rich Bank 1Learn More Fixes
Throttle/Pedal Position Sensor/Switch D/E Voltage CorrelationLearn More Fixes
Bank 1 Air/Fuel Ratio ImbalanceLearn More Fixes
GMC is a premium brand of cars run by General Motors using the platforms of its other brands Chevrolet, Buick and Cadillac.
GMC models tend to be slightly more upmarket than Chevrolet but usually less luxurious than Cadillac.
As the technology is shared among these companies you can expect to see them share common fault codes among the models.
One of the most common GMC error codes to appear on your model is going to be the P1870. This P1870 error code is triggered by a component slipping in the automatic transmission. The computer that controls the automatic transmission keeps track of many components in the unit through sensors and if one of these sensors falls out of range then you can expect to see this code appear on an OBD2 reader.
Alongside that error code could also be the U0073 warning. This is caused by a lack of communication between the ECU and the PCM (a device that controls the fuel intake system). It is most likely that alongside this error you are experiencing a change in the behavior of the engine.
Another common Ford fault code is P0443 – signifying a problem with the purge control valve. This purge control valve is responsible for ensuring that fuel vapors do not escape into the atmosphere. It is controlled by an electronic solenoid which can become faulty along with the wiring and the module that controls these components too.
- Models: 5