The instrument cluster stores diagnostic trouble codes (DTCs) as a current or history DTC. If the instrument cluster detects a system malfunction, the instrument cluster will only store a DTC that corresponds to that particular malfunction. If a current DTC is stored and the fault is no longer present, some DTCs will remain current until the first ignition cycle. Other DTCs will go into history when the fault is no longer present and does not require an ignition cycle. History DTCs are intermittent malfunctions and must be diagnosed differently than current DTCs. Refer to Intermittents and Poor Connections Diagnosis for more information.

Diagnostic trouble codes (DTCs) can be read using a scan tool. There are no provisions for flash code diagnostics. Refer to the scan tool user's manual for specific scan tool instructions.

The following features are accessible through a scan tool:

Ensure that the scan tool is capable of interfacing with this vehicle before attempting to communicate with the instrument cluster. In order to use the scan tool, connect the scan tool to the data link connector (DLC), and turn the ignition switch to the ON position. The scan tool reads serial data sent through the Class 2 serial data link from the instrument cluster harness connector terminal B1 to the DLC terminal 2.