C-10 ~ Air Conditioning Clutch Control

A/C Circuit:

Chart C-10 A/C Functional Check:

Circuit Description
When the Air Conditioning (A/C) diagnostic test mode is selected, the Engine Control Module (ECM) will supply a ground to the A/C clutch relay. Battery positive voltage is then supplied to the A/C clutch through the completing of circuit through the thermo switch relay, which is part of the A/C "ON/OFF" switch circuit. If the A/C system exhibits high pressure or an overheating condition exist, the A/C system will be disabled by the open of the A/C high pressure switch or the A/C thermo switch.


Diagnostic Aids
The A/C high pressure switch is located in the high pressure side A/C hose.
The thermo cut-out switch is part of the A/C evaporator mounted under the dash. For further information about the A/C system, refer to Heating and Ventilation.