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Pinpoint Test D: The Tire Pressure Monitoring System Warning Indicator Is ON Continuously and "Low tire pressure" displays




Tire Pressure Monitoring System (TPMS)

Pinpoint Test D: The Tire Pressure Monitoring System (TPMS) Warning Indicator Is ON Continuously and The Message Center Displays LOW TIRE PRESSURE

Normal Operation

The Tire Pressure Monitor (TPM) module monitors the air pressure of all 4 road tires. The wheel-mounted tire pressure sensors transmit data via radio frequency signals to the TPM (Tire Pressure Monitor) module. The TPM (Tire Pressure Monitor) module is a radio receiver that collects the air pressure data from the Tire Pressure Monitoring System (TPMS) tire pressure sensors. The data is then sent to the Body Control Module (BCM) where a predetermined pass/fail criteria is applied. The TPMS (Tire Pressure Monitoring System) sensor radio transmissions are sent approximately once every 60 seconds when the vehicle speed exceeds 32 km/h (20 mph). The BCM (Body Control Module) compares each TPMS (Tire Pressure Monitoring System) sensor transmission against a low-pressure limit. If it has been determined that the tire pressure has fallen below this limit, the BCM (Body Control Module) communicates this on the vehicle communication bus to the Instrument Panel Cluster (IPC). The IPC (Instrument Panel Cluster) then illuminates the TPMS (Tire Pressure Monitoring System) warning indicator and displays the appropriate message(s) in the message center.

This symptom can also be caused by a spare tire currently being used in place of a road tire. Make sure that the spare tire is not currently in use. On vehicles with different front and rear tire pressures, if the sensors are not trained following a tire rotation, this symptom may result. Advise the customer that on vehicles with different front and rear tire pressures, the sensors must be trained as directed in the Owner's Literature.

This pinpoint test is intended to diagnose the following:

- Spare tire currently in use

- Tire pressure not set to specifications listed on the Vehicle Certification (VC) label

- TPMS (Tire Pressure Monitoring System) sensors not trained following tire rotation

- TPMS (Tire Pressure Monitoring System) sensor(s)

PINPOINT TEST D : THE TPMS (Tire Pressure Monitoring System) WARNING INDICATOR IS ON CONTINUOUSLY AND THE MESSAGE CENTER DISPLAYS LOW TIRE PRESSURE

NOTE:
Use only the Digital Tire Pressure Gauge any time tire pressures are measured to be sure that accurate values are obtained.
NOTE:
If a warranty case is opened for an actual TPMS (Tire Pressure Monitoring System) fault, document and include the actual tire pressure data in all warranty communications.

D1 CHECK FOR LOW TIRE PRESSURE

- Using the Digital Tire Pressure Gauge, measure and record the air pressure in all 4 tires.

- Adjust the pressure for those found to be below the specification listed on the VC (Vehicle Certification) label.

- Activate each sensor at least twice with the training tool or customer activation tool to make sure the TPM (Tire Pressure Monitor) module gets the latest air pressure data. Refer to Tire Pressure Monitoring System (TPMS) Sensor Activation or drive the vehicle for at least 2 minutes above 32 km/h (20 mph) to clear the low pressure warning. Do not train the sensors at this time.

Has the TPMS (Tire Pressure Monitoring System) warning indicator gone out?

Yes
The system is operating correctly at this time. The concern was caused by low tire pressure.
No
GO to D2.

D2 CHECK FOR SPARE TIRE IN USE
NOTE: The spare tire is not programmable even if it is equipped with a TPMS (Tire Pressure Monitoring System) sensor. If a damaged road wheel is located in the cargo area, the sensor may still be recognized by the TPMS (Tire Pressure Monitoring System) as low. Make sure the spare tire is not currently in use. To restore TPMS (Tire Pressure Monitoring System) functionality, repair the damaged road wheel and re-mount it to the vehicle.

- Check spare tire location.

Is the spare tire in use?

Yes
REPAIR and REMOUNT the wheel to the vehicle. REFER to Wheel and Tire . ADJUST tire pressures to the required pressure as defined on the VC (Vehicle Certification) label located in the driver door jam.
No
GO to D3.

D3 CHECK IF THE TIRES WERE ROTATED WITHOUT TPMS (Tire Pressure Monitoring System) SENSOR TRAINING
NOTE: If the TPMS (Tire Pressure Monitoring System) sensors at the front of the vehicle are still trained in the rear positions but inflated to the front air pressures, the TPMS (Tire Pressure Monitoring System) warning indicator illuminates continuously.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BCM (Body Control Module).

- Monitor and record the following BCM (Body Control Module) PIDs:
- Left Front Tire Pressure (TPM_PRES_LF)

- Right Front Tire Pressure (TPM_PRES_RF)

- Left Rear Tire Pressure (TPM_PRES_LRO)

- Right Rear Tire Pressure (TPM_PRES_RRO)


Do the rear PIDs show front air pressures and the front PIDs show rear air pressures?

Yes
The tires have been rotated without training the sensors. TRAIN the sensors. REFER to Tire Pressure Monitoring System (TPMS) Sensor Training .
No
GO to D4.

D4 CHECK FOR STUCK TPMS (Tire Pressure Monitoring System) SENSOR

- Monitor and record the following BCM (Body Control Module) PIDs:
- Left Front Tire Pressure (TPM_PRES_LF)

- Right Front Tire Pressure (TPM_PRES_RF)

- Left Rear Tire Pressure (TPM_PRES_LRO)

- Right Rear Tire Pressure (TPM_PRES_RRO)


- Using the Digital Tire Pressure Gauge, measure the actual tire pressures.

- Compare the air pressure PIDs with the actual air pressures.

Do the compared tire pressure values match within ± 5 psi?

Yes
REFER to Instrument Panel, Gauges and Warning Indicators to diagnose the TPMS (Tire Pressure Monitoring System) warning indicator is always on.
No
INSTALL a new TPMS (Tire Pressure Monitoring System) sensor(s) for the sensor(s) in question. REFER to Tire Pressure Monitoring System (TPMS) Sensor .