hey guys i really need help........ my 2003 grand caravan radiator fans wont work. right now i have them hot wired to a switch but i dont like the idea of it.

background...

where to begin. i have replaced the coolant temp sensor twice and still have the same problem. i checked it with the multimeter and the voltage does change as the temp increases. i have also replaced the relay and the 40amp fuse in the block. i do notice that when the engine is running i get about 6.2 volts going to the radiator fans if they are disconnected but as soon as i plug the pigtails in the voltage drops. there is 12v going into the relay and if i jump the connection the fans run. this may be confusing so msg me if u need me to clarify anything. i really would like a wiring diagram of the fan system with voltages but can not find any.. please any help is greatly appreciated

 

Replace the fan relay. Its in the front bumper fascia on the passager side. You'll need to remove the fascia.

 

Already Replaced it but the fans still don't work. When I disconnect the coolant temp sensor the fans don't run and the same goes if I turn on the a/c. Could there be an I line fuse somewhere? If I had a shop manual or a wiri g diagram with the voltages it might help

 

Is the CEL on?

I am having trouble posting the diagram for you .....

To get you going ..
terminals at relay
1- org/red wire 12v from 40amp fuse
2-dkblu/dkgrn 12v to fans
3-dkblu/vio signal from PCM
4- blk/dkgrn ground -relay and fans

I agree the relay is suspect- new does NOT mean good.
you might try using a DVOM selecting A/C and probing terminal 3 for voltage...checking for command from PCM

LET us know

 

1- org/red wire 12v from 40amp fuse
2-dkblu/dkgrn 12v to fans
3-dkblu/vio signal from PCM
4- blk/dkgrn ground -relay and fans

k ill have to take the fascia off this week. its been a cpl weeks since i had it off but heres what i remember ill post the other voltages when i get it off.

1- org/red wire 12v from 40amp fuse---12v
2-dkblu/dkgrn 12v to fans---6.2v (but when i plug in the fans the voltage is 0v
3-dkblu/vio signal from PCM-----
4- blk/dkgrn ground -relay and fans----0v

 

disregard my last post here are the voltages i get

1- org/red wire 12v from 40amp fuse---13.26v
2-dkblu/dkgrn 12v to fans--6.02v (0v when i plug the pigtails into the fans)
3-dkblu/vio signal from PCM----0v
4- blk/dkgrn ground -relay and fans---13.26v (if this is the wire all the way on the opposite side of the org/red wire

 

im guna assume that there is a short somewhere between the computer and the ground or even a bad ground

 

If you probe the fan circuit (#2) be sure to unplug the fan -
this will seperate wiring from the motors.

what about the question is the cel on?


ARe you back probing? or probing just harness?
ck terminal #4 -eng off- for ground.

 

The CEL is on i cleared the codes but still get 2 codes saying that the coolant temp sensor voltage is to high and too low. i have replaced the coolant temp sensor twice so i dont know why it would be saying that.

the fan circuit shows 6.02 volts when the fans are unplugged. when i plug the fans back in the voltage is 0v. i was probing the wires right off the harness while it was plugged in.

this may sound stupid but how do i check for ground with my multi meter?

 

The codes are 1st step now.
post the code #s pxxxx- sometimes confusion as to description and many eyes will catch that

with the harness connected to module and probing the circuit is backprobing ....

doing this- with engine running what is activity on PCM circuit with A/C on and then off?

Disconnect BOTH ends of circuit...confirm meterr* ...one probe to ggouund other probe to wire ... any reading other than infinity is
suspect..

*touch probes together checking tool watching for reading..