2006 Caravan OBD code P0480

Obd Code P0480 on Dodge

Engine Cooling Fan Not Coming ON.

Temp gauge jumps high with A/C running

United States 2006 Dodge Caravan Vehicle.

Q: 2006 Caravan with code P0480. Replaced fan relay, thermostat, coolant sensor, and tested fan motors (fans run on direct connect to battery).

Fans will not kick on and temp gauge hits top end if running A/C...otherwise gauge holds at about mid-level.


A: There are few possibilities to cause such problems.
Some wiring and component testing is required.

Make sure you have a test light or voltmeter to do some simple testing at the relay which controls Fan.

Locate the fan relay in engine fuse box.Then unplug the relay and test it's power and ground feed.

HOW TO TEST FAN RELAY:

Ground the black meter lead or the alligator clip end of your test light and probe the orange/red wire in the relay connector and make sure the test light lights up.

Then take the meter lead or alligator clip to battery positive and probe the black/dark green wire and make sure it lights up.

If all checks out ok then use jumper trick.Jumper trick helps to confirm the problem with relay or its faulty fan.


Where To Use jumper wire:
With the relay plugged back in and the fans plugged in, insert a straightened paperclip into the back side of the relay connector on the dark blue/violet wire. If you attach a jumper wire between the paperclip and ground it should cause the fans to run at full speed. Properly inspect Does this allow the fans to run?
If no then it can be faulty relay or fan motor.

If both fans came on when I touched to ground

That means the relay is good,and the wiring from the relay to the fans is good.

Testing PCM:

Next is to test PCM. You need to go to the powertrain control module (PCM), which is located in the front of the left front wheel. You'll have to pull back the wheel well liner to access it. There locate the dark blue/violet wire there which should be in pin 6 of the black/white connector. There is a discrepancy in the wire color so I'd like to pop the back cover off the connector and check the wire color. It will be in the top row and should be dark blue/violet, but may be brown/violet.

Once  located the correct wire  jump it to ground the same way as at the relay and see if the fans come on.
Make sure you do this with ignition OFF.

If fans are not coming ON.
Then next step is Bypassing the PCM module

Bypassing the wiring thru the power module

For this go back a little way from the connector and strip a small section of the wire, plug the connector back in and run a temporary jumper wire between there and the relay. At the relay connect the wire to the dark blue/violet wire.

Then clear the code, start the engine and turn on the a/c to see if the fans work again.

As per schematics the wire is br/vt going into module and then db/vt coming out to relay.Inspect this wire and connect jumper between this wire.
Many a times this wire gets cut or crimped in between causing such problem.

This details will help.
Thanks.