Pinpoint Tests AA: The Tire Pressure Monitoring System (TPMS) Warning Indicator Is Never/Always On

Instrumentation, Message Center and Warning Chimes

Pinpoint Tests

Pinpoint Test AA: The Tire Pressure Monitoring System (TPMS) Warning Indicator Is Never/Always On

Normal Operation

The Instrument Cluster (IC) 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 IC to turn the TPMS warning indicator on. If a TPMS fault condition exists, the SJB sends a message to the IC to flash the TPMS warning indicator. If the TPMS status message is missing for less than 5 seconds, the IC defaults the TPMS warning indicator to the last setting (on or off), based upon the last known good message received. If the TPMS status message is missing for more than 5 seconds, the IC sets DTC U0140 and flashes the TPMS indicator for approximately 75 seconds then turns on the indicator steady.

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.

This pinpoint test is intended to diagnose the following:

- TPMS concern
- SJB
- IC



PINPOINT TEST AA: THE TPMS WARNING INDICATOR IS NEVER/ALWAYS ON

-------------------------------------------------
AA1 CHECK THE TIRE PRESSURE


- Verify that the tire pressure in all tires meets the recommended tire pressures on the vehicle certification label. Refer to Vehicle/Application and ID.
- Do all the tires meet the recommended tire pressures?

Yes
GO to AA2.

No
CORRECT the tire pressures. TEST the system for normal operation.

-------------------------------------------------
AA2 CARRY OUT THE INSTRUMENT INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger.
- Select the TPMS warning indicator (TIRE_PRES) active command. Command the TPMS warning indicator on and off. Observe the TPMS warning indicator.
- Does the TPMS warning indicator illuminate when commanded on and turn off when commanded off?

Yes
GO to AA3.

No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.

-------------------------------------------------
AA3 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND IC SELF-TESTS


- Check for recorded IC DTCs from the continuous and on-demand self-tests.
- Are any DTCs recorded?

Yes
For DTC U0140, Go To Pinpoint Test AH. Pinpoint Tests AH: DTC U0140

For all other DTCs, REFER to DTC Charts. Instrumentation, Message Center and Warning Chimes

No
GO to AA4.

-------------------------------------------------
AA4 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND SJB SELF-TESTS


- Check for recorded SJB DTCs from the continuous and on-demand self-tests.
- Are any DTCs recorded?

Yes
REFER to Body Control Systems.

No
INSTALL a new SJB. TEST the system for normal operation.

-------------------------------------------------