A/C Signal: Description and Operation

AIR CONDITIONING CYCLING SWITCH
The Air Conditioning Cycling Switch (ACCS) is a voltage signal input to the Powertrain Control Module (PCM) which indicates when the A/C is requested. When the A/C demand switch is turned On and both the ACCS and the high pressure contacts of the A/C Pressure Switch (ACPSW) (if equipped) are closed, voltage is supplied to the ACCS circuit signal at the PCM. If the ACCS signal is not received by the PCM, the Wide Open Throttle A/C Cut-Off (WAC) circuit will not allow the A/C to operate.







AIR CONDITIONING PRESSURE SENSOR
The Air Conditioning Pressure (ACP) sensor is located in the high pressure (discharge) side of the air conditioning A/C system. The ACP sensor provides a voltage signal to the Powertrain Control Module (PCM) that is proportional to the A/C head pressure. The PCM uses this information for A/C clutch control, cooling fan control and idle speed control.


A/C WIDE OPEN THROTTLE (WOT) RELAY
The A/C clutch control relay is used to improve idle smoothness after engine start-up and to improve acceleration performance. The A/C is cut off for approximately five seconds just after the engine is started and when the Throttle Position (TP) sensor indicates a WOT condition.