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 Switch (Cruise Control): Testing and Inspection


1. Disconnect vacuum hose from valve and connect a suitable vacuum pump with an integral gauge to valve.
2. With pedal in released position, apply approximately 14 inches of vacuum to valve, then observe gauge.
3. If valve loses more than 5 inches of vacuum in one minute, valve is defective.
4. With vacuum applied to valve, depress pedal. If valve does not release vacuum when pedal is depressed, valve is defective.