Hello everyone,

I am getting a p0480 code on my 2004.5 truck - from my understanding this pertains to the cooling circuit with respect to the viscous clutch fan.

About a year ago, I added a clutch fan switch - when turned "on" the switch is grounding the green wire at the clutch fan connector. This switch has worked in the past and has come in very handy for me when the tranny temps get hot - for some reason I have never heard the truck's fan ever kick in on it's own.

I am leaving in a couple of weeks to FL with the 34' car trailer and it seems my switch is not working. I did verify that the ground connection with the switch is working.

Does anything else have to be present besides the green wire being grounded to activate the viscous clutch fan 100%?

Someone mentioned on a previous post to check the resistance of the upper two wires to the right on the clutch fan connector with the tab up. If this is correct can somone post a picture or drawing of the connector / even better state the color of the wires to check the resistance?

Lastly, I see northern auto sells a replacement viscous clutch fan - how many hours does it take to replace the unit? What is all entailed?

Since my clutch fan never seemed to work in the past, is there a temperature switch I can replace / check to see if that has gone bad.


Thanks for all your support.

Scott

 

Ok - so I drive today to go drop the truck off at a service center to look at a noise in the front end and during my 20 min drive the fan locked up with my cheater switch "on" which manually calls for the viscous fan to engage.

What this tells me is that grounding the green wire alone does not lock up the fan - must be another control mechanism such as tranny temp. I looked at the tranny temp gauge when I heard the fan noise and it was just coming off of the lowest temp therefore around 110f

I am glad the cheater switch is working