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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Switch Operation

Switch Operation



1) When MODE switch is set to "MAX A/C," "A/C", "DEF/HEAT" or "DEF," air conditioning system relay activates to enter a signal into engine control unit. This turns on both compressor clutch and F.l.C.D. (Fast Idle Control Device). At this point, the main and sub fans also operate. Blower relay operates to direct the air flowrate determined by FAN switch position.
2) Thermostat activates to stop compressor clutch, F.I.C.D., and main and sub fans.
3) When "High-Low" pressure switch operates, compressor clutch and F.l.C.D. stop but main and sub fans are operating.
4) When fan control switch operates, both main and sub fans operate rapidly.




1. Operation Of Major Components (Mode Switch "ON")





2. Operation Of Major Components (Control Switch "ON")