Diagnosis on the Tire Pressure Monitor (TPM) system is done by reading DTC stored in the receiver's memory. TPM DTCs can only be displayed through the Instrument Panel Cluster (IPC) display (on-board diagnostic capabilities), or by using a scan tool. Most all information in this section will refer to the scan tool for diagnostic support. Refer to Scan Tool Diagnostics . The TPM system relies on the same receiver as the Remote Function Actuation (RFA) system, therefore TPM DTCs will be displayed in addition to RFA DTCs. For more information on the RFA system. Refer to Remote Keyless Entry Diagnostic Information in Keyless Entry.

The TPM system uses information from other systems in order to execute some functions. Therefore, before further diagnosis, review the general information on how the TPM system operates and how each system interacts with the TPM. For example, the TPM system uses barometric pressure information from the Powertrain Control Module (PCM) to compensate for different altitudes. If tire pressure readings are inaccurate a good starting point would be to monitor barometric pressure readings from the PCM. This can determine if the PCM is sending the correct barometric pressure data to the TPM system.

Use a scan tool in order to diagnose the TPM system when referred to in diagnostic procedures. In addition to displaying DTCs, the TPM system displays the input status and the data values used. Any of these features can be selected using the scan tool.

Become very familiar with the TPM system capabilities and diagnostic features. These self-diagnostic features are referenced in the DTC tables and are very useful in diagnosing non-DTC setting malfunctions as well.

Replace the receiver only if the diagnostic procedures specifically direct you to do so. Check for wiring problems first. Then check the system for further problems. Most system malfunctions are traceable to faulty wiring and connectors, and occasionally components. The receiver very reliable and not the likely cause of a system malfunction. Receiver replacement before a complete diagnosis will usually result in a recurrence of the original complaint malfunction.

The TPM system does not have an indicator lamp or a specific message in order to indicate a malfunction. When the TPM system indicates a malfunction, the receiver sends a message through the serial data line to the IPC to display the SERVICE TIRE WARN SYS message. Further diagnosis of the TPM system is done through reading the DTCs or through the use of a scan tool.

The TPM system stores DTCs as either current or history codes. DTCs for the TPM system are accessed through RFA system. Most TPM system malfunctions will set a DTC and display the SERVICE TIRE WARN SYS message on the IPC. Other TPM malfunctions will only set a DTC and not display a fault message and must be read using a scan tool. History DTCs are intermittent malfunctions and be diagnosed different then current DTCs. Refer to Testing for Intermittent Conditions and Poor Connections .