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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Brake Signal: Description and Operation

The brake light switch is used as an engine controller input to signal deceleration and full stop conditions. Along with other inputs, the engine controller uses brake switch input to maintain idle speed by controlling the Automatic Idle Speed (AIS) motor position. The brake switch is located on the brake pedal support bracket.