Chart 8 Defogger on Continuously

Chart 8:

Electrical Schematic:

CIRCUIT DESCRIPTION
The programmer provides a ground for the defogger relay when it receives a command from the Climate Control Panel (CCP) via the data line. The Body Control Module (BCM) 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. Checks to see if circuit 291 is grounded.
2. Checks for a short to voltage on circuit 293.
3. Checks to see if the programmer is grounding circuit 291.