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)

Or, hide this message: temporarily or permanently

Air Conditioning (A/C) Clutch Relay

Fig. 19 Power Distribution Center (PDC):






OPERATION
The PCM controls the air conditioning clutch relay ground circuit. Buss bars in the Power Distribution Center (PDC) supply voltage to the solenoid side and power side of the relay. When the PCM receives an air conditioning input, it grounds the A/C compressor clutch relay and the radiator fan relay.

When the PCM senses low idle speeds or wide open throttle through the throttle position sensor, it removes the ground for the A/C compressor clutch relay.

When the relay de-energizes, the contacts open preventing air conditioning clutch engagement.

Also, if the PCM senses a part throttle launch condition, it disables the A/C compressor clutch for several seconds.

The air conditioning clutch relay is located in the PDC (Fig. 19). The inside top of the PDC cover has a label showing relay and fuse location.