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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Power Supply Control

POWER SUPPLY CONTROL
When the ECM receives an ON signal emitted from the ignition switch, current flows through the main relay. This turns the ignition relay ON so that power is supplied to the fuel injectors, mass air flow sensor, idle air control valve, etc.