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 Signal: Description and Operation

The brake switch signal is produced by the brake light switch mounted under the dash assembly. It sends a 12 volt signal to ECU terminal C10 whenever the brake pedal is depressed. The signal is processed by the ECU to modify output to the idle and charging circuits.