Pinpoint Test 46: The Tire Pressure Monitoring System (TPMS) Warning Indicator Is Never/Always On
PINPOINT TEST 46: THE TIRE PRESSURE MONITORING SYSTEM (TPMS) WARNING INDICATOR IS NEVER/ALWAYS ON
Normal Operation
The instrument cluster receives the tire pressure monitoring system (TPMS) messages from the smart junction box (SJB) over the medium speed controller area network (MS-CAN) communication bus. If the SJB determines that the tire pressure has exceeded the low tire pressure limits, a message is sent to the instrument cluster to turn on the TPMS warning indicator. If a TPMS fault condition exists, the SJB sends a message to the instrument cluster to flash the TPMS warning indicator. If the TPMS status message is missing for more than 5 seconds, the instrument cluster sets DTC U0140 and flashes the TPMS indicator for approximately 75 seconds then turns on the indicator.
NOTE:If DTC U0140 is set in the SJB, other symptoms may also be present such as high beam indicator, RH/LH turn indicators, instrument panel backlighting, and door ajar indication.
Possible Causes
- Tire pressure
- TPMS concern
- SJB
- Instrument cluster
Diagnostic Procedure
