Chart 6 Rear Defog "ON" Continuously

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

The ACP provides a ground for the defogger relay when it receives a command from the Instrument Panel Cluster (IPC) via the data line. The IPC times the operation initially for 10 minutes, then commands the programmer to deactivate the relay ground. Additional requests for rear defogger are for 5 minute intervals, thereafter until a new ignition cycle occurs.


TEST DESCRIPTION

Numbers below refer to circled numbers on the diagnostic chart.

1. This step eliminates a short to voltage on CKT 840, 293, or 676.

2. This step checks the relay coil resistance. Diminished resistance may be caused by a faulty ACP.

3. This step distinguishes between a short to ground on CKT 291 and a faulty ACP