Cadillac ATS Warning Lights: What They Mean

Other warnings and indicators

Airbag Readiness Light

If it stays on after starting or comes on while driving, the airbag system may not be working properly and airbags might not inflate correctly.
What to do: Have the vehicle serviced right away. PDF page 120

Engine Coolant Temperature Warning Light

The engine has overheated. Driving with this light on can damage the engine.
What to do: Pull over and turn off the engine as soon as possible. PDF page 126

Antilock Brake System (ABS) Warning Light

Antilock brakes are not working; regular brakes still work unless the brake system warning light is also on, which indicates a regular brake problem.
What to do: Stop safely, turn off and restart the engine. If the light stays on or returns, have the vehicle serviced. PDF page 124

Service Electric Parking Brake Light

A problem exists with the Electric Parking Brake or another system that is reducing parking brake performance. The vehicle can still be driven.
What to do: Take the vehicle to a dealer as soon as possible. PDF page 124

Traction Control System (TCS)/StabiliTrak Light

Steady: TCS and possibly StabiliTrak/ESC are disabled. Flashing: the TCS and/or StabiliTrak/ESC system is actively working.
What to do: Check the DIC messages to see which feature is not functioning and whether service is needed. PDF page 126

Traction Off Light

Traction Control System has been turned off, so wheel spin is not limited. It also comes on when StabiliTrak/ESC is turned off.
What to do: Adjust driving accordingly. PDF page 125

StabiliTrak OFF Light

StabiliTrak/ESC is turned off, which also turns TCS off, so the system does not help control the vehicle. It may also come on in some Performance Traction modes.
What to do: Turn on TCS and StabiliTrak/ESC and the light turns off. PDF page 125

Passenger Airbag Status Indicator

ON means the front passenger frontal and knee airbags may inflate; OFF means the passenger sensing system has turned them off.
What to do: If both lights stay on or neither lights after several seconds, see your dealer for service. PDF page 120

Green: system on

Vehicle Ahead Indicator

Green when a vehicle is detected ahead; amber when you are following a vehicle ahead much too closely. PDF page 125

Summarized in our own words from the 2019 Cadillac ATS 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.