Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Heated Element: Description and Operation

Circuit Description
The BCM controls the operation of the rear window defogger and outside mirror defogger through the defogger relay coil control. When the rear window defogger switch is depressed (ON) and the engine is running, the defogger relay coil is energized through the BCM for 20 minutes. Battery voltage is supplied to the rear window defogger through the defogger relay contacts.