A/C Compressor

PRINCIPLE OF OPERATION, A/C COMPRESSOR





A/C Compressor--is activated, either from the ACC control module or by means of the A/C button on the dashboard, battery positive is applied to pin 59 of the Trionic control module. The control module then opens the idle air control valve slightly more to prepare for the imminent increase in engine load. After a short delay the control module grounds pin 54 which is connected to the A/C relay.

The control module breaks the circuit to pin 54 if the engine has still not been started.

Cars with ETS--When the A/C compressor is activated, either from the ACC control module or by means of the A/C button on the dashboard, battery positive is applied to pin 37 of the ETS control module. The ETS system then opens the throttle slightly more to prepare for the imminent increase in engine load. After a short delay the electronic throttle system (ETS) control module grounds pin 38, causing the A/C relay to operate.

The ETS control module breaks the circuit to pin 38 if the engine has still not been started.

Pin 59 of the Trionic control module is connected to pin 38 of the ETS control module. This enables a richer mixture to be delivered briefly to the engine when the A/C compressor is activated. This function is not activated on Trionic M1994-95.