GMC Sierra Denali Warning Lights: What They Mean

Red: stop or act now

Brake System Warning Light

Comes on when the parking brake is set or doesn't fully release; if it stays on after release or while driving, the brakes have a problem.
What to do: Pull off the road and stop carefully. If the light is still on, have the vehicle towed for service. PDF page 118

Other warnings and indicators

Airbag Readiness Light

If it comes on and stays on, something may be wrong with the airbag system.
What to do: Have the vehicle serviced right away. PDF page 115

Charging System Light

If it stays on or comes on while driving, there may be a problem with the electrical charging system; the battery could drain.
What to do: Have it checked by your dealer. If you must drive a short distance, turn off all accessories like the radio and air conditioner. PDF page 115

Antilock Brake System (ABS) Warning Light

Antilock brakes are not functioning if it stays on or comes on while driving; regular brakes still work if it is the only light on.
What to do: Stop safely, turn off the vehicle and restart. If the light stays on or returns, have the vehicle serviced. If the brake light is also on, see your dealer. PDF page 118

Low Tire Pressure Warning Light

One or more tires are significantly under-inflated. If it flashes about a minute then stays on, the tire pressure monitor system has a malfunction.
What to do: Stop as soon as possible and inflate tires to the pressure on the Tire and Loading Information label. PDF page 305

Traction Control System (TCS)/StabiliTrak® Light

Steady means TCS and possibly StabiliTrak are disabled. Flashing means the TCS and/or StabiliTrak is actively working.
What to do: Check the DIC messages to see which feature isn't working and whether the vehicle needs service. PDF page 120

StabiliTrak® OFF Light

StabiliTrak is turned off, which also turns off TCS, so the system does not assist in controlling the vehicle.
What to do: Turn on TCS and StabiliTrak to turn the light off. If it doesn't come on briefly at start, have the vehicle serviced. PDF page 120

Traction Off Light

The Traction Control System has been turned off, so wheel spin is not limited.
What to do: Adjust driving accordingly. PDF page 120

Passenger Airbag Status Indicator

ON means the front passenger airbag is enabled; OFF means the sensing system turned it off. Both lit or neither lit suggests a problem.
What to do: If both or no lights stay on after several seconds, see your dealer for service. PDF page 115

Four-Wheel-Drive Light

The transfer case is shifted into four-wheel drive and the front axle engages; LO or HI shows the range. PDF page 118

Summarized in our own words from the 2016 GMC Sierra Denali owner's manual (AI-assisted; every light name was matched against its cited page 2026-10-18). Your vehicle may not have every light, and other years can differ. A red warning that stays on usually means stop safely and check: your manual has the final word.