Chart 9 - Defogger Inoperative
CHART 9 DEFOGGER INOPERATIVEECC SYSTEM CHECK MUST BE PERFORMED FIRST
CIRCUIT DESCRIPTION
The programmer provides a ground for the defogger relay when it receives a command from the Electronic Climate Control Panel (ECCP) via the data line. The 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. This step checks to see if the rear defogger relay is receiving power.
2. This step checks to see if the circuit breaker is receiving power.
3. This step checks to see if the programmer is grounding the rear defogger relay coil.
4. This step bypasses the rear defogger relay to see if the grid will operate.