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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Control Module HVAC: Description and Operation

Idle Speed Increase Via Diode Matrix

Diode Matrix (V2):

A control voltage from the blower regulator greater than 2.5 volts will increase the engine idle speed via the diode matrix (V2).