Diagnostic Trouble Codes (DTCS)

Diagnostic trouble codes (DTCs) indicate that the instrument panel cluster (IPC) has detected a malfunction in a particular circuit or system. The IPC is programmed with routines for internal tests that are followed only under prescribed test conditions. When these conditions exist, the IPC tests certain circuits or systems for malfunctioning. When a fault condition is true, a DTC is set current. Some DTCs command the IPC to illuminate the SERVICE VEHICLE SOON indicator.

DTCs are not stored in the IPC's EEPROM and so are not retained after a battery disconnection.