2003 Dodge A/C fan problems

[russell8]

My A/C fan quit working about a month ago. I have checked all fuses & relays. The fan does work but is not getting a ground signal from the relay so I have had to jump the relay and the fan stays on all the time now. I have had the truck put on 2 different scan tools and they cannot figure out the problem. I also have a friend with the identical truck so we switched out computers and that didnt fix the problem. So as you can see I am about to pull my hair out here. Oh yeah it does give a code P0480 and if anybody knows what that is or can help me out in any way please give me a shout. Engine light stays on all the time.

[791ton]

P0480 = Cooling fan 1 control circuit

Cooling Fan Control Operation:Reads the temperature of the coolant and passes the information to the engine control computer (ECC). The ECC receives analog information and signals the cooling fan switch to cycle the cooling fan on or off, as required.


OR

Cooling Fan Switch Operation:The cooling fan switch on electric fans monitors coolant temperature signals from the engine control computer. When the engine is cool, the switch opens to keep the fan from spinning. When engine is warm, the switch closes to turn fan on for cooling.

When testing a cooling fan switch, first test it with the engine cold, then test it when the engine reaches a specified temperature. Check your vehicle's service manual for more directions.
To check a switch, disconnect the connector at the switch. With an ohmmeter, check for continuity between the terminals of the switch with the switch moved to the on position and to the off position.



The continuity through a switch can be checked with an ohmmeter. With the switch open, there should be infinite resistance. With the switch closed, there should be zero resistance.

With the switch off, there should be no continuity between the terminals. With the switch on, there should be good continuity between the terminals. If the switch is activated by something mechanical and doesn't complete the circuit when it should, check the adjustment of the switch. (Some switches are not adjustable.) If the adjustment is correct, replace the switch. Another way to check a switch is to simply bypass it with a jumper wire. If the component works when the switch is jumped, a bad switch is indicated.
Voltage drop across switches should also be checked. Ideally, when the switch is closed there should be no voltage drop. Any voltage drop indicates resistance and the switch should be replaced.

[russell8]

Thanks for the info. This is an 03 Dodge truck, do you happen to know where this circuit is located. I have called the dealership and they dont even no what this part is so if you can tell me where it is or even a part # that would be great. A service tech. told me I would just need to replace the fan motor and replace the pigtail but I think he is full of $#@!. I put the fan off of my friends truck and of course it did not fix it so you can see where I am with this problem.

[dthomas27]

I am also having this same problem with my 03 ram 1500. Engine light is on, code scanned was P0480. A/C fan does not work. When idling the A/C is also not getting cold. When I am driving the A/C gets nice and cold. Also the A/C pump kick's on and off very often. When I put Power from the battery to the fan itself the fan spins. Can Anyone Help with this problem. Is it possible that I just need to have the system charged with frion or whatever.

[shader]

I am also having this problem. Local shop tells me this is common and wanted $400 for p&l. Says my freon level is adequate, and that the fan housing, fan blade and wiring pigtail are one piece assembly and all have to be replaced together. I am going to keep the a/c on while driving 35mph or more, and windows down at the stoplights until I get time to replace myself. My question is, can I direct wire this with a switch to the dash in the mean time?

2003 Dodge Ram 4.7L P/U