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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Brake On/Off Switch

PURPOSE
The Brake ON/OFF (BOO) Switch signals shift lock actuator when brake pedal has been depressed.

The BOO switch deactivates the speed control system when brake pedal is depressed.

The BOO switch signals 4 wheel anti-lock brake system module that the braking condition is about to occur.

The BOO switch is closed with brake pedal depressed, and allows current to flow to the operated stop lamps.