Engine Speed Sensor (8.3, 9 Liter) or Cam Sensor (15 Liter) is failed
Odd clutch solenoid coil or its wiring shorted to power
Aux 4th remote valve FLOW potentiometer is failed in the Armrest Controller
Evaporator sensor open or shorted to power
Engine Speed Sensor signal is failed (no signal at engine controller pin A17)
Odd clutch solenoid coil or its wiring shorted to power
If Air conditioning does not work,possible causes are blown fuse, faulty wiring or loose connections, fxan belt loose or slipping or defective switch or defective compressor clutch.