DTC Display and Reset Procedures

The C5 has hundreds of DTCs (Diagnostic Trouble Codes).
The codes can be read from the DIC's 20 character display. Here is how:

1. Turn ignition ON, engine OFF.

2. Press the RESET button to acknowledge any warning messages that may be present.

3. Press the OPTIONS button on the Driver Information Center (DIC) and hold.

4. While holding the OPTIONS button, press the FUEL button 4 times with a 10 second period.

5. System will enter the automatic display mode.

The DTCs are arranged by systems as follows:

PCM - Powertrain Control Module
TCS - Traction Control System
RTD - Real Time Damping
BCM - Body Control Module
IPC - Instrument Panel Cluster
RADIO -Radio
HVAC - Heater, Ventilation and Air Conditioning
LDCM - Left Door Control Module
RDCM - Right Door Control Module
SCM - Seat Control Module
RFA - Remote Function Actuation

Automatic display mode, shows codes (if any) for each of the above systems and then stops in manual display mode. Manual mode can be entered at any time by pressing any key except E/M.

In manual display mode, the keys operate as follows:

FUEL - Previous DTC
GAGES - Next DTC
TRIP - Previous System
OPTIONS - Next System
E/M - Exit Diagnostics
RESET - Clear DTCs

The DTC's are needed by your dealer for diagnostics. SO do not reset unless you know you created them.