How to Reset the Tire Pressure Light (TPMS) on a Cadillac ATS

1. Set the parking brake and place the vehicle in Service Mode.
2. Turn on the Tire Pressure info display option, then scroll to the Tire Pressure screen with the five-way DIC control.
3. Press and hold SEL in the center of the five-way DIC control until the horn sounds twice and TIRE LEARNING ACTIVE shows.
4. Hold the relearn tool against the driver side front tire sidewall near the valve stem and press its button until the horn chirps.
5. Repeat at the passenger side front, passenger side rear, then driver side rear tire.
6. Turn the vehicle off and set all four tires to the pressure on the Tire and Loading Information label.

• You have two minutes for the first tire and five minutes overall for all four, or the process stops and must be restarted.
• Two horn sounds after the driver side rear tire mean matching is finished and TIRE LEARNING ACTIVE goes off.

Source: 2019 Cadillac ATS owner's manual, PDF pages 295, 296. Steps are summarized in our own words (AI-assisted, checked against the cited pages 2026-10-18). Other model years can differ; your manual has the final word.