Cadillac CT6 Warning Lights: What They Mean

Red: stop or act now

Brake System Warning Light

Brake problem if it stays on at start-up; may also show with parking brake set, low brake fluid, or severely faded brakes.
What to do: If it comes on while driving, pull off the road and stop carefully. If still on, have the vehicle towed for service. PDF page 126

Engine Coolant Temperature Warning Light

The engine has overheated; driving with it on can damage the engine.
What to do: Pull over and turn off the engine as soon as possible. PDF page 130

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 74

Other warnings and indicators

Antilock Brake System (ABS) Warning Light

ABS is not working if the light stays on or returns; with the brake light also on, the regular brakes have a problem too.
What to do: Stop safely, turn the vehicle off and on to reset. If it stays on or returns, see your dealer for service. PDF page 127

Charging System Light

If it stays on or comes on while driving, there may be a problem with the electrical charging system. PDF page 123

Electric Parking Brake Light

Parking brake is applied. Continued flashing after release or while driving means a problem with the electric parking brake system.
What to do: If the light does not come on or keeps flashing, see your dealer. PDF page 126

Service Electric Parking Brake Light

If it stays on, the electric parking brake system needs service.
What to do: Take the vehicle to a dealer as soon as possible. PDF page 127

Traction Control System (TCS)/StabiliTrak Light

Steady: TCS and possibly StabiliTrak/ESC are disabled. Flashing: the system is actively working.
What to do: Check DIC messages to see which feature is not working and whether service is needed. PDF page 129

Traction Off Light

Traction control has been turned off; wheel spin is not limited. It also shows when StabiliTrak/ESC is off.
What to do: Adjust driving accordingly. PDF page 129

StabiliTrak OFF Light

StabiliTrak/ESC is turned off, which also turns off TCS, so the system does not assist in controlling the vehicle.
What to do: Turn TCS and StabiliTrak/ESC back on to turn off the light. PDF page 129

Passenger Airbag Status Indicator

ON means the front passenger airbags may inflate; OFF means the sensing system turned them off.
What to do: If both or neither light stay on after several seconds, see your dealer for service. PDF page 123

Gear Shifting Light

Shows when Performance Algorithm Liftfoot or Performance Algorithm Shift is activated. PDF page 127

Driver Mode Control Light

Shows when Sport Mode, Snow/Ice Mode or Track Mode is selected. PDF page 130

Summarized in our own words from the 2020 Cadillac CT6 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.