3000GT Convertible V6-2972cc 3.0L DOHC Turbo 24 Valve (1996)
A/C Signal: Description and Operation
PURPOSE/OPERATION
When the driver turns on the A/C system, a positive voltage signal is supplied to the 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.