System Check Chart C-1

You have been sent to this chart because the odometer relays correct mileage, both the IPC and CCDIC displays work, "ENGINE CONTROL SYSTEM FAULT" lights during cranking, and pressing the "OFF" and "WARMER" buttons does not result in diagnostic mode.

NOTE: The following step numbers refer to circled numbers on diagnostic chart. See Fig 1 . For climate control button identification, see Fig 2 .

This checks for operation of the off and climate control buttons. If the "OFF" or other buttons do not respond, go to CHART C-2 .
This checks the operation of the "WARMER" (red) button.
If both the "OFF" and "WARMER" buttons work at one time and diagnostics is still not entered, replace the CCDIC (combo panel).

Fig 1: Identifying Chart C-1 Flow Chart

Courtesy of GENERAL MOTORS CORP.

Fig 2: Identifying Climate Control Buttons

Courtesy of GENERAL MOTORS CORP.