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Low Tire Pressure Indicator Malfunction

Low Tire Pressure Indicator Malfunction

Diagnostic Instructions


Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.


Circuit/System Description

If the body control module (BCM) detects a low tire pressure condition or a malfunction in the system, the module will send a serial data message to the instrument cluster requesting the appropriate tire pressure monitor indicator illumination and also to display the appropriate data message on the driver information center, if equipped. If a significantly low tire pressure is detected, the tire pressure monitor indicator is permanently ON. If the system is affected, the tire pressure monitor indicator will flashes for 1 minute and then remain illuminated after Ignition ON.

Diagnostic Aids


Both the indicator icon and driver information center message can be cleared by adjusting the tire pressures to the recommended kPa/PSI and driving the vehicle above 40 km/h (25 MPH) for at least 2 minutes.

If unsure about the condition, cycle the ignition and observe the tire pressure monitor indicator icon. If the tire pressure monitor indicator icon is continuously illuminated after the instrument cluster bulb check is completed, a low tire pressure condition is present. Check the tires for damage or leaks and inflate to the tire placard specifications. If the tire pressure monitor indicator icon flashes for 1 min. after the instrument cluster bulb check is completed and then remains illuminated, a tire pressure monitor system DTC is set. Perform the Diagnostic System Check - Vehicle .

Aftermarket wheel valve system locations can cause a sensor to not function correctly.

A sensor may have been damaged due to a previous wheel/tire service or flat tire event.

The use of tire sealants can obstruct the sensor pressure sensing port and cause inaccurate tire pressure readings. If this condition is verified, remove the sealer from the tire and replace the sensor. Refer to Tire Pressure Indicator Sensor Replacement .

Occasionally sensor transmissions are not received by the remote function receiver module due to vehicle level radio frequency interference from items such as but not limited to aftermarket ignition systems, DVD players, CB radios, or metallic type window tinting.


Reference Information

Schematic Reference

Tire Pressure Monitoring System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Tire Pressure Monitor Description and Operation

Electrical Information Reference


Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs


Scan Tool Reference

Control Module References

Circuit/System Testing

Note

Low tire pressure in one or more tires is indicated by a continuously illuminated tire pressure monitor indicator icon after the instrument cluster bulb check is completed. If equipped with a driver information center, a check tire pressure type message will also be displayed. It is not necessary to perform the learn procedure for a low tire condition.

When a tire pressure monitor system DTC is set, the tire pressure monitor indicator icon will flash for 1 minute after the instrument cluster bulb check is completed and then remains illuminated. If equipped with a driver information center, a service tire monitor type message will also be displayed.



1. Verify all tires are inflated to the proper pressure +/-10%. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label .

2. If not within the specified range, adjust all tire pressures to specification and drive the vehicle over 40 km/h (25 MPH) for greater than 2 min. Verify the tire pressure monitor indicator icon is OFF.

3. Using a scan tool, perform the instrument panel special functions All Indicators test. Command the instrument panel lamps ON and OFF. Verify the tire pressure monitor indicator icon turns ON and OFF.

4. If the tire pressure monitor icon does not turn ON and OFF, replace the P16 Instrument Cluster.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References