Stealth V6-2972cc 3.0L SOHC (1995)
A/C Signal: Description and Operation
Air Conditioning Switch And Relay Circuit
OPERATION
When the driver turns on the A/C system, a positive voltage signal is supplied to the Engine Control Module (ECM) (as an indication that the A/C
system is needed) and to one side of the A/C relay coil, located on the LH inner fender panel. The ECM determines if engine conditions are
suitable for A/C operation (engine temperature, idle speed, ignition timing and air/fuel mixture).
If the the engine coolant temperature switch is closed (temp. below 235° F) the A/C ON signal is transmitted to the ECM. If the ECM senses that
conditions are suitable for A/C operation, it supplies the ground circuit for the A/C relay coil, energizing it. This allows the relay to supply voltage
to the compressor clutch.
