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

Instrumentation, Message Center and Warning Chimes

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

Normal Operation

The Instrument Panel Cluster (IPC) 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 (Smart Junction Box) determines that the tire pressure has exceeded the low tire pressure limits, a message is sent to the IPC (Instrument Panel Cluster) to turn the TPMS (Tire Pressure Monitoring System) warning indicator on. If a TPMS (Tire Pressure Monitoring System) fault condition exists, the SJB (Smart Junction Box) sends a message to the IPC (Instrument Panel Cluster) to flash the TPMS (Tire Pressure Monitoring System) warning indicator for 75 seconds then the IPC (Instrument Panel Cluster) turns the indicator on steady. If the TPMS (Tire Pressure Monitoring System) is in the TPMS (Tire Pressure Monitoring System) sensor training mode, the SJB (Smart Junction Box) sends a command to the IPC (Instrument Panel Cluster) to flash the TPMS (Tire Pressure Monitoring System) warning indicator throughout the procedure.

If the TPMS (Tire Pressure Monitoring System) status message is missing or invalid for less than 5 seconds, the IPC (Instrument Panel Cluster) defaults the TPMS (Tire Pressure Monitoring System) warning indicator to the last setting (on or off), based upon the last known good message received. If the TPMS (Tire Pressure Monitoring System) status message is missing for more than 5 seconds, DTC U0140:00 sets and the TPMS (Tire Pressure Monitoring System) warning indicator flashes for approximately 75 seconds then turns the indicator on steady. If the message is invalid for more than 5 seconds, the IPC (Instrument Panel Cluster) sets DTC U0430:068 (non-hybrid) or U0422:68 (hybrid) and flashes the TPMS (Tire Pressure Monitoring System) warning indicator for approximately 75 seconds then turns the indicator on steady.

NOTE: If DTC U0140:00 is set in the SJB (Smart Junction Box) , other symptoms may also be present such as high beam indicator, RH/LH turn indicators, instrument panel backlighting, and door ajar indicator.

This pinpoint test is intended to diagnose the following:

- Tire pressure

- TPMS (Tire Pressure Monitoring System) concern

- SJB (Smart Junction Box)

- IPC (Instrument Panel Cluster)

PINPOINT TEST AC : THE TPMS (Tire Pressure Monitoring System) WARNING INDICATOR IS NEVER/ALWAYS ON

AC1 CHECK THE TIRE PRESSURE

- Verify that the tire pressure in all tires meets the recommended tire pressures on the vehicle certification label.

Do all the tires meet the recommended tire pressures?

Yes
GO to AC2.

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

AC2 CARRY OUT THE IPC (Instrument Panel Cluster) INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: IPC (Instrument Panel Cluster) DataLogger.

- Select the TPMS (Tire Pressure Monitoring System) warning indicator (TPMWARN_LMP) active command. Command the TPMS (Tire Pressure Monitoring System) warning indicator on and off while observing the TPMS (Tire Pressure Monitoring System) warning indicator.

Does the TPMS (Tire Pressure Monitoring System) warning indicator illuminate when commanded on and turn off when commanded off?

Yes
GO to AC3.

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

AC3 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST

- Check for recorded IPC (Instrument Panel Cluster) DTCs from the continuous self-test.

Are any DTCs recorded?

Yes
For DTC U0430:68 or DTC U0422:68, RETRIEVE and REPAIR all non-network DTCs in the SJB (Smart Junction Box) and all other modules on the network. REFER to Body Control Systems for a list of all DTCs.

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

No
GO to AC4.

AC4 RETRIEVE THE RECORDED DTCs FROM THE SJB (Smart Junction Box) SELF-TEST

- Check for recorded DTCs from the SJB (Smart Junction Box) self-test.

Are any DTCs recorded?

Yes
REFER to Body Control Systems for correct navigation of the DTC.

No
INSTALL a new SJB (Smart Junction Box). TEST the system for normal operation.