GMC Warning Lights and Meanings
Complete guide to GMC dashboard warning lights and symbols. Learn what each indicator means and what action you should take when they illuminate.
Understanding GMC Dashboard Warning Lights
GMC vehicles are equipped with an advanced diagnostic system that monitors various components and systems. When an issue is detected, a corresponding warning light will illuminate on your dashboard.
These warning lights are color-coded to indicate the severity of the issue:
- Red: Indicates a serious issue that requires immediate attention. You should stop driving as soon as it's safe to do so.
- Amber/Yellow: Suggests a less urgent problem that should be checked soon, but doesn't require immediate action.
- Green: Usually informational, indicating that a system is active or functioning normally.
- Blue: Usually informational, indicating features like high beam headlights or coolant temperature.
- White: Usually informational, indicating that certain systems or features are currently active.
Below you'll find a comprehensive list of warning lights that may appear on your GMC vehicle's dashboard.
GMC Warning Light Categories
Critical Warning Lights
These red warning lights indicate serious issues that require immediate attention.
Service Warning Lights
These amber/yellow lights suggest issues that need attention soon but aren't immediately critical.
Information Indicators (Green)
These green lights simply inform you that certain systems are active.
Information Indicators (Blue)
These blue lights indicate that certain features or systems are enabled.
Information Indicators (White)
These white lights provide status information about various vehicle systems.
Critical Warning Lights
Airbag Readiness Light
This light shows if there is an electrical problem with the airbag system. The system check includes the airbag sensor(s), the passenger sensing system, the pretensioners, the airbag modules, the wiring, and the crash sensing and diagnostic module. The airbag readiness light comes on for several seconds when the vehicle is started. If the light does not come on then, have it fixed immediately.
Brake System Warning Light
This light should come on briefly when the vehicle is turned on. If it does not come on then, have it fixed so it will be ready to warn you if there is a problem. If the light comes on and stays on at start-up, there is a brake problem. Have the brake system inspected right away. If the light comes on while driving, pull off the road and stop carefully. If equipped with an electric brake boost, vehicle speed may be limited when the brake system warning light comes on. The brake pedal might be harder to push, or the brake pedal may go closer to the floor. It could take longer to stop. If the light is still on, have the vehicle towed for service.
Brake System Warning Light
This light should come on briefly when the vehicle is turned on. If it does not come on then, have it fixed so it will be ready to warn you if there is a problem. If the light comes on and stays on at start-up, there is a brake problem. Have the brake system inspected right away. If the light comes on while driving, pull off the road and stop carefully. If equipped with an electric brake boost, vehicle speed may be limited when the brake system warning light comes on. The brake pedal might be harder to push, or the brake pedal may go closer to the floor. It could take longer to stop. If the light is still on, have the vehicle towed for service.
Brake System Warning Light
This light should come on briefly when the vehicle is turned on. If it does not come on then, have it fixed so it will be ready to warn you if there is a problem. If the light comes on and stays on at start-up, there is a brake problem. Have the brake system inspected right away. If the light comes on while driving, pull off the road and stop carefully. If equipped with an electric brake boost, vehicle speed may be limited when the brake system warning light comes on. The brake pedal might be harder to push, or the brake pedal may go closer to the floor. It could take longer to stop. If the light is still on, have the vehicle towed for service.
Brake System Warning Light
This light should come on briefly when the vehicle is turned on. If it does not come on then, have it fixed so it will be ready to warn you if there is a problem. If the light comes on and stays on at start-up, there is a brake problem. Have the brake system inspected right away. If the light comes on while driving, pull off the road and stop carefully. If equipped with an electric brake boost, vehicle speed may be limited when the brake system warning light comes on. The brake pedal might be harder to push, or the brake pedal may go closer to the floor. It could take longer to stop. If the light is still on, have the vehicle towed for service.
Charging System Light
The charging system light comes on briefly when the ignition is turned on, but the engine is not running, as a check to show the light is working. The light turns off when the engine is started. If it does not, have the vehicle serviced by your dealer. If the light stays on, or comes on while driving, there may be a problem with the electrical charging system. Have it checked by your dealer. Driving while this light is on could drain the battery. When this light comes on, the Driver Information Center (DIC) also displays a message. If a short distance must be driven with the light on, be sure to turn off all accessories, such as the radio and air conditioner.
Door Ajar Light
This light comes on when a door is open or not securely latched. Before driving, check that all doors are properly closed.
Door Ajar Light
This light comes on when a door is open or not securely latched. Before driving, check that all doors are properly closed.
Electric Parking Brake Light
This light comes on when the parking brake is applied. If the light continues flashing after the parking brake is released, or while driving, there is a problem with the Electric Parking Brake system. A message may also display in the Driver Information Center (DIC). If the light does not come on or remains flashing, see your dealer.
Electric Parking Brake Light
This light comes on when the parking brake is applied. If the light continues flashing after the parking brake is released, or while driving, there is a problem with the Electric Parking Brake system. A message may also display in the Driver Information Center (DIC). If the light does not come on or remains flashing, see your dealer.
Electric Parking Brake Light
This light comes on when the parking brake is applied. If the light continues flashing after the parking brake is released, or while driving, there is a problem with the Electric Parking Brake system. A message may also display in the Driver Information Center (DIC). If the light does not come on or remains flashing, see your dealer.
Engine Coolant Temperature Light
This light comes on briefly while starting the vehicle. If it does not, have the vehicle serviced by your dealer. If the system is working normally the indicator light goes off.
Engine Oil Pressure Light
Oil pressure can vary with engine speed, outside temperature, and oil viscosity. On some models, the oil pump will vary engine oil pressure according to engine needs. Oil pressure may change quickly as the engine speed or load varies. This is normal. If the oil pressure warning light or Driver Information Center (DIC) message indicates oil pressure outside the normal operating range, check the vehicle’s oil as soon as possible. This light should come on briefly as the engine is started. If it does not come on, have the vehicle serviced by your dealer. If the light comes on and stays on, it means that oil is not flowing through the engine properly. The vehicle could be low on oil and might have some other system problem. See your dealer.
Front Passenger Seat Belt Reminder
When the vehicle is started, this light flashes and a chime may come on to remind passengers to fasten their seat belts. Then the light stays on solid until the belt is buckled. This cycle continues several times if the front passenger remains or becomes unbuckled while the vehicle is moving. If the front passenger seat belt is buckled, neither the chime nor the light comes on. The front passenger seat belt reminder light and chime may come on if an object is put on the seat such as a briefcase, handbag, grocery bag, laptop, or other electronic devices. To turn off the reminder light and/or chime, remove the object from the seat or buckle the seat belt.
Pedestrian Ahead Indicator
If equipped, this indicator will display amber when a nearby pedestrian is detected in front of the vehicle.
Seat Belt Reminder
When the vehicle is started, this light flashes and a chime may come on to remind the driver to fasten their seat belts. Then the light stays on solid until the belt is buckled. This cycle may continue several times if the driver remains or becomes unbuckled while the vehicle is moving. If the driver seat belt is buckled, neither the light nor the chime comes on.
Security Light
The security light should come on briefly as the engine is started. If it does not come on, have the vehicle serviced by your dealer. If the system is working normally, the indicator light turns off. If the light stays on and the engine does not start, there could be a problem with the theft-deterrent system.
Service Warning Lights
Antilock Brake System Warning Light
This warning light should come on briefly when the vehicle is turned on. If the light does not come on, have it fixed so it will be ready to warn if there is a problem. If the light comes on while driving, safely stop as soon as it is possible and turn off the vehicle. Then turn on the vehicle again to reset the system. If the ABS warning light stays on, or comes on again while driving, the vehicle needs service. A chime may also sound when the light stays on. If the ABS warning light is the only light on, the vehicle has regular brakes, but ABS is not functioning. If both the ABS warning light and the brake system warning light are on, ABS is not functioning and there is a problem with the regular brakes. See your dealer for service.
FCA/ACC Following Gap Light
If equipped, this light indicates the following gap setting (near, medium, or far) for FCA, and, if equipped, Adaptive Cruise Control (ACC).
Lane Departure Warning Light
This light is green if LDW is on and ready to operate. This light changes to amber and flashes to indicate that the lane marking has been crossed without using a turn signal in that direction.
Lane Keep Assist Light
After the vehicle is started, this light turns off and stays off if LKA has not been turned on or is unavailable. LKA may assist by gently turning the steering wheel if the vehicle approaches a detected lane marking. The LKA light is amber when assisting. This light flashes amber as a Lane Departure Warning (LDW) alert, to indicate that the lane marking has been crossed. LKA will not assist or alert if the turn signal is active in the direction of lane departure, or if LKA detects that you are accelerating, braking, or actively steering.
Low Fuel Warning Light
A Low Fuel Warning Light near the fuel gauge comes on briefly when the ignition is turned on as a check to show it is working. It also comes on when the fuel gauge indicator nears empty. The light turns off when fuel is added. If it does not, have the vehicle serviced.
Malfunction Indicator Lamp
If the light is flashing: A malfunction has been detected that could damage the emission control system and increase vehicle emissions. Diagnosis and service may be required. To help prevent damage, reduce vehicle speed and avoid hard accelerations and uphill grades. If towing a trailer, reduce the amount of cargo being hauled as soon as possible. If the light continues to flash, find a safe place to park. Turn the vehicle off and wait at least 10 seconds before restarting the engine. If the light is still flashing, follow the previous guidelines and see your dealer for service as soon as possible. If the light is on steady: A malfunction has been detected. Diagnosis and service may be required. Check the following: ● If fuel has been added to the vehicle using the capless fuel funnel adapter, make sure that it has been removed. The diagnostic system can detect if the adapter has been left installed in the vehicle, allowing fuel to evaporate into the atmosphere. A few driving trips with the adapter removed may turn off the light. ● Poor fuel quality can cause inefficient engine operation and poor driveability, which may go away once the engine is warmed up. If this occurs, change the fuel brand. It may require at least one full tank of the proper fuel to turn the light off. If the light remains on, see your dealer.
Passenger Airbag Status Indicator
When the vehicle is started, the passenger airbag status indicator will light ON and OFF, or the symbol for on and off, for several seconds as a system check. Then, after several more seconds, the status indicator will light either ON or OFF, or either the on or off symbol, to let you know the status of the front outboard passenger frontal airbag. If the word ON, or the on symbol, is lit on the passenger airbag status indicator, it means that the front outboard passenger frontal airbag is allowed to inflate. If the word OFF, or the off symbol, is lit on the passenger airbag status indicator, it means that the passenger sensing system has turned off the front outboard passenger frontal airbag. If, after several seconds, both status indicator lights remain on, or if there are no lights at all, there may be a problem with the lights or the passenger sensing system. See your dealer for service.
Passenger Airbag Status Indicator
When the vehicle is started, the passenger airbag status indicator will light ON and OFF, or the symbol for on and off, for several seconds as a system check. Then, after several more seconds, the status indicator will light either ON or OFF, or either the on or off symbol, to let you know the status of the front outboard passenger frontal airbag. If the word ON, or the on symbol, is lit on the passenger airbag status indicator, it means that the front outboard passenger frontal airbag is allowed to inflate. If the word OFF, or the off symbol, is lit on the passenger airbag status indicator, it means that the passenger sensing system has turned off the front outboard passenger frontal airbag. If, after several seconds, both status indicator lights remain on, or if there are no lights at all, there may be a problem with the lights or the passenger sensing system. See your dealer for service.
Passenger Airbag Status Indicator
When the vehicle is started, the passenger airbag status indicator will light ON and OFF, or the symbol for on and off, for several seconds as a system check. Then, after several more seconds, the status indicator will light either ON or OFF, or either the on or off symbol, to let you know the status of the front outboard passenger frontal airbag. If the word ON, or the on symbol, is lit on the passenger airbag status indicator, it means that the front outboard passenger frontal airbag is allowed to inflate. If the word OFF, or the off symbol, is lit on the passenger airbag status indicator, it means that the passenger sensing system has turned off the front outboard passenger frontal airbag. If, after several seconds, both status indicator lights remain on, or if there are no lights at all, there may be a problem with the lights or the passenger sensing system. See your dealer for service.
Service Electric Parking Brake Light
On some vehicles, the service electric parking brake light should come on briefly when the vehicle is started. If it does not come on, have it fixed so it will be ready to warn if there is a problem. For vehicles with the reconfigurable cluster, this light may not come on when the vehicle is started. If this light stays on, the vehicle should be taken to a dealer as soon as possible.
StabiliTrak OFF Light
This light comes on briefly while starting the engine. If it does not, have the vehicle serviced by your dealer. This light comes on when the StabiliTrak/ Electronic Stability Control (ESC) system is turned off. If StabiliTrak/ESC is off, the Traction Control System (TCS) is also off. If StabiliTrak/ESC and TCS are off, the system does not assist in controlling the vehicle. Turn on the TCS and the StabiliTrak/ESC systems, and the warning light turns off.
Tire Pressure Light
For vehicles with the Tire Pressure Monitor System (TPMS), this light comes on briefly when the engine is started. It provides information about tire pressures and the TPMS. When the Light Is On Steady This indicates that one or more of the tires are significantly underinflated. A Driver Information Center (DIC) tire pressure message may also display. Stop as soon as possible, and inflate the tires to the pressure value shown on the Tire and Loading Information label. When the Light Flashes First and Then Is On Steady If the light flashes for about a minute and then stays on, there may be a problem with the TPMS. If the problem is not corrected, the light will come on at every ignition cycle.
Tow/Haul Mode Light
For vehicles with the Tow/Haul Mode feature, this light comes on when the Tow/ Haul Mode has been activated.
Traction Control System Light
This light comes on briefly when the engine is started. If the light does not come on, have the vehicle serviced by your dealer. If the system is working normally, the indicator light turns off. If the light is on and not flashing, the TCS and potentially the StabiliTrak/ESC system have been disabled. A Driver Information Center (DIC) message may display. Check the DIC messages to determine which feature(s) is no longer functioning and whether the vehicle requires service. If the light is on and flashing, the TCS and/ or the StabiliTrak/ESC system is actively working.
Traction OFF Light
This light comes on briefly while starting the engine. If it does not, have the vehicle serviced by your dealer. If the system is working normally, the indicator light then turns off. The traction off light comes on when the Traction Control System (TCS) has been turned off by pressing and releasing the TCS/StabiliTrak/Electronic Stability Control (ESC) button. If the TCS is off, wheel speed will be limited when necessary to protect the driveline from damage. Adjust driving accordingly. This light and the StabiliTrak OFF light come on when StabiliTrak/ESC is turned off.
Vehicle Ahead Indicator
If equipped, this indicator will display amber when you are following a vehicle ahead much too closely.
Information Indicators (Green)
Adaptive Cruise Control Light
This light is white when the Adaptive Cruise Control (ACC, if equipped) is on and ready, and turns green when the ACC is set and active.
Cruise Control Light
The cruise control light is white when the cruise control is on and ready, and turns green when the cruise control is set and active.
Four-Wheel-Drive Light
If equipped, the four-wheel-drive light displays what mode the vehicle is in. The light will show each mode: 2WD, 4HI, AUTO (all transfer cases), 4LOW, and N (two-speed transfer case only). The light will flash when a shift is in progress. Once the shift is complete the light will be steady.
Front Fog Lamp Light
The fog lamp light comes on when the fog lamps are in use. The light goes out when the fog lamps are turned off.
Hill Descent Control Light
If equipped, the Hill Descent Control light comes on when the system is ready for use. When the light flashes, the system is active.
IntelliBeam Light
This light comes on when the IntelliBeam system, if equipped, is enabled.
IntelliBeam Light
This light comes on when the IntelliBeam system, if equipped, is enabled.
Lamps On Reminder
This light comes on when the exterior lamps are in use, except when only the Daytime Running Lamps (DRL) are active.
Lane Departure Warning Light
This light is green if LDW is on and ready to operate.
Lane Keep Assist Light
After the vehicle is started, this light turns off and stays off if LKA has not been turned on or is unavailable. If equipped, this light is green if LKA is turned on and is ready to assist.
Off-road Mode Control Light
This light comes on when Off-Road Mode is selected.
Snow Mode Control Light
This light comes on when Snow/Ice Mode is selected.
Sport Mode Control Light
This light comes on when Sport Mode is selected.
Terrain Mode Control Light
This light comes on when Terrain Mode is selected.
Vehicle Ahead Indicator
If equipped, this indicator will display green when a vehicle is detected ahead and amber when you are following a vehicle ahead much too closely.
Information Indicators (Blue)
High-Beam On Light
This light comes on when the high-beam headlamps are in use.
Information Indicators (White)
Adaptive Cruise Control Light
This light is white when the Adaptive Cruise Control (ACC, if equipped) is on and ready, and turns green when the ACC is set and active.
Cruise Control Light
The cruise control light is white when the cruise control is on and ready, and turns green when the cruise control is set and active.
Four Corner Air Suspension Light
This light comes on when the air suspension is in Service Mode or Alignment Mode.
Four Corner Air Suspension Light
This light comes on when the air suspension is raised to increased ground clearance height. It will flash green and give an alert to indicate that the vehicle is changing to a higher ride height.
Four Corner Air Suspension Light
This light comes on when the air suspension is raised to maximum ground clearance height.
Four Corner Air Suspension Light
This light comes on when the air suspension is lowered for easy entry and exit from the vehicle. It will flash green and give an alert to indicate that the vehicle is changing to a lower ride height.
Gear Shifting Light
If equipped, this light will display when Performance Algorithm Liftfoot (PAL) is activated.
Lane Keep Assist Light
After the vehicle is started, this light turns off and stays off if LKA has not been turned on or is unavailable. If equipped, this light is white if LKA is turned on, but not ready to assist.
Trailer Sway Control Light
This light will flash when Trailer Sway Control is active.
Service StabiliTrak Light
This light comes on when there is a problem with the StabiliTrak system.