The old fan problem...P0480 code..

[Deac1234]

I know this topic has been beaten to death but I've tried searching and get conflicting advice... comments... help!

Problem: car displays a code of p0480 (low speed fan error)

Problem. If the air is on, when starting the car it will throw a P0480 code within a minute or two.

If the air is off, it will take about a mile or two before throwing the code.

Car does NOT overheat and air seems to work, though cooling suffers sitting at a light.

Checked both relays and they seem to be ok. I also jumped the contacts in the relay sockets and the fan seems to run normally.

The fan comes on shortly after starting the car if the air is on but I'm not sure what speed it's running at.

I really need accurate fan operation information. Should the low speed fan come on immediately when the air is turned on? If not, when? How does the computer know that there is a problem with the low speed fan?

I'm wondering if I really have a fan problem , or a false code error? Can the fan be bad and still run when run when tested manually? Replacing the fan/relay asm is an expensive 'guess' I'd prefer to be able to prove the problem is there. Also the fan asm is N/A from Chrysler

Car is a 2006, touring convertible turbo with about 97,000 miles on it.

Thanks for any help!

[rsrocket1]

The P0480 code is thrown when the fan relay circuit does not detect enough current flowing through the relay coil when the relay is commanded on. I noticed that when bypassing the control signal and controlling the relay with a switch wired to the inside of the car. I solved that by putting a 100 Ohm resistor across the coil terminals of the relay and energizing the relay through the switch. I only did that while waiting for a new fan from Rock Auto.

[ptcruisersteve]

I would suggest checking the radiator plug contacts to make sure you are getting good contacts. Some members have come across radiator plug contacts that have been arcing or one of the pins have been pushed in.

[pt06]

deac; the air conditioning high pressure switch will turn on the high speed radiator fan relay. This takes a few seconds. You should easily hear the fan running when it is on high speed. The fan is barely audible when it is on low speed. Sticking a straw into the fan blades [be careful] or a dab of white on a fan blade might help.

The factory fan assy. had a 'fan module' mounted at the bottom of the radiator. It contained the relays. Aftermarket fan assys. usually had 2 relays mounted to the passenger side of the radiator shroud.

When you jumped the fan relays you should have heard the 2 speeds of the fan.
Cooling should not change while sitting at a light.

My recommendation is to clean/check/and lube the three grounds on the inner fenders. There are 2 on the left fender and especially the 1 on the right front fender which is difficult to see and get to. ---- All are 5/16" hex head sheet metal screws.

[Deac1234]

PT06,

Thanks for the help. Do you know the relay control signal sequence?

Does the computer turn the low speed fan for low speed and then turn it off and switch to the high speed relay to activate it or does it turn BOTH relays on for high speed? I don't know what the low speed fan is actually for. When should it come on?

Thanks,

Kerry

[rsrocket1]

From the Gen 2 Service manual



Although most have said and mine does this too:

The high speed fan turns on when the A/C is on at any speed and any temperature. Only one relay and one set of brushes are powering the fan at any time. Low or high.

[rckstein]

Originally Posted by rsrocket1

From the Gen 2 Service manual



Although most have said and mine does this too:

The high speed fan turns on when the A/C is on at any speed and any temperature. Only one relay and one set of brushes are powering the fan at any time. Low or high.

Chrysler should have just gone with a 1-speed fan, at all times when it's needed, it's on at high speed. What does the low speed really accomplish except to cause other error codes and fan problems.

[ptcruisersteve]

Originally Posted by rckstein

Chrysler should have just gone with a 1-speed fan, at all times when it's needed, it's on at high speed. What does the low speed really accomplish except to cause other error codes and fan problems.

One of the reasons the low speed was designed was to reduce fan noise.

[rckstein]

Originally Posted by ptcruisersteve

One of the reasons the low speed was designed was to reduce fan noise.

Do you hear the fan running when you're in the car with the a/c and stereo on? The sound of the fan running is of no bother to me.