Diagnosis on the RFA system is done by reading DTC stored in the receiver's memory. RFA 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 RFA system and Tire Pressure Monitor (TPM) system both rely on the same receiver, therefore TPM DTCs will be displayed in addition to RFA DTCs. For more information on the TPM system. Refer to Tire Pressure Monitor System Description in Tire Pressure Monitor.

The RFA system uses information from other systems in order to execute some functions. Therefore, before further diagnosis, review the general information on how the RFA system operates and how each system interacts with the RFA system. Refer to Keyless Entry System Description . This will save diagnostic time, future misdiagnosis, and unnecessary parts replacement.

Use a scan tool in order to diagnose the RFA system when referred to in diagnostic procedures. In addition to displaying DTCs, the RFA 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 RFA 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 is 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 RFA system does not have an indicator lamp or a specific message in order to indicate a malfunction. When the RFA 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 RFA system is done through reading the DTCs or through the use of a scan tool.

The RFA system stores DTCs as either current or history codes. DTCs for the TPM system are also accessed through the RFA system. Most RFA system malfunctions will set a DTC and display the SERVICE TIRE WARN SYS message on the IPC. Other RFA 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 Intermittents and Poor Connections .