brentbiely

Trying to troubleshoot fan clutch operation. Anybody know which wire or pin is used for the signal for the clutch to turn on, or increase speed?

Spooler

Do a search. A guy rigged up a switch to make it come on when on. You should be able to find it.

GreyTD

On an 04 it is pin #1 on connector by shroud. Put it to ground. The fan speed will increase in a couple of mins according to manual. It will set a code though.

brentbiely

I'll try that and see what happens. The service manual I have makes reference to the signal from the ECM being a Pulse Width Modulated signal. That makes me think that I have to hook up a 'scope to the signal line to see if the signal changes when the A/C is turned on.

I get the impression from digging through the forums that there may be problems with the ECM not sending the correct signal, so the fan doesn't turn on in time to prevent the condensor from overheating.

Thanks for the help folks!

GreyTD

If the ecm was not sending correct signal, it would not receive correct signal, it would than set the code DTC 0480. which is the same code that you will set when shorting pin 1 to grd. You can verify code by turning key on/off 3X ending in the on position while watching odometer.

Jonesey

Mine threw a P0483 cooling fan speed code. Anyone know what this one means?

GreyTD

The ecm is not seeing an increase in fan speed as requested. Either your fan clutch is gone bad or the wires going to the fan clutch have been ripped/cut; common problem. Check the wires as they go up from the bottom of shroud to center of fan hub. Also check connector for corrosion(sp?)