Cadillac XT4 Owner Manual (GMNA-Localizing-MidEast-13527545) - 2020 -CRC - 9/16/19262 VEHICLE CAREIf the tire is overinflated by more than35 kPa (5 psi), the horn will soundmultiple times and the turn signallamp will continue to flash for severalseconds after filling stops. To releaseand correct the pressure, while theturn signal lamp is still flashing,briefly press the center of the valvestem. When the recommendedpressure is reached, the hornsounds once.If the turn signal lamp does not flashwithin 15 seconds after starting toinflate the tire, the tire fill alert hasnot been activated or is not working.If the hazard warning flashers are on,the tire fill alert visual feedback willnot work properly.The TPMS will not activate the tire fillalert properly under the followingconditions:. There is interference from anexternal device or transmitter.. The air pressure from the inflationdevice is not sufficient to inflatethe tire.. There is a malfunction inthe TPMS.. There is a malfunction in the hornor turn signal lamps.. The identification code of theTPMS sensor is not registered tothe system.. The battery of the TPMS sensoris low.If the tire fill alert does not operatedue to TPMS interference, move thevehicle about 1 m (3 ft) back orforward and try again. If the tire fillalert feature is not working, use a tirepressure gauge.TPMS Sensor Matching ProcessEach TPMS sensor has a uniqueidentification code. The identificationcode needs to be matched to a newtire/wheel position after rotating thevehicle’s tires or replacing one or moreof the TPMS sensors. The TPMSsensor matching process should alsobe performed after replacing a sparetire with a road tire containing theTPMS sensor. The malfunction lightand the DIC message should go off atthe next ignition cycle. The sensorsare matched to the tire/wheelpositions, using a TPMS relearn tool,in the following order: driver sidefront tire, passenger side front tire,passenger side rear tire, and driverside rear tire. See your dealer forservice or to purchase a relearn tool.There are two minutes to match thefirst tire/wheel position, andfive minutes overall to match all fourtire/wheel positions. If it takes longer,the matching process stops and mustbe restarted.The TPMS sensor matching process is:1. Set the parking brake.2. Place the vehicle in ServiceMode. See Ignition Positions0 168.3. Make sure the Tire Pressure infopage option is turned on. Theinfo pages on the DIC can beturned on and off through theOptions menu. See DriverInformation Center (DIC) 0 122.