Cooling fan problem

[Bigjohnjr]

Have a 1993 Plymouth Grand Voyager Le (130000) miles on it. On the way to work, got stuck in traffic and temp gauge peged and van overheated a bit. The check gauge light came on.

Had the van towed to a local shop, the guy checked it out and told me that the fan was no good. I got a used one from a local junkie and put it in.

I ran the van and the fan never comes on, even when the A/C is turned on.

I got a wireing diagram and checked some voltages and this is what I got.

The gray wire is at 12volts. good!
the dk blue is at 12volts. good!
There is 0 volts at the fan, both lt green and dk green. Bad!

I would assume that the hight speed is for the A/C?
and low speed is normal.


I took the wire from the temp gauge near the thermastat and grounded it to the engine and peged the temp gauge and still no fan.

I am lost...

any ideas?

[m_motorsports]

I found a broken wire to the fan relay after getting a code indicating a problem to that circuit... It is under the air filter intake. Have you actually tested the new fan by hot wiring it directly to 12v?

[slantsixness]

FAN relay?

The sensor goes to the Computer (SMEC) and then sends a signal to the fan relay. The A/c relay is separate, and has a different relay (high speed, like you thought). The relays, and the wiring to them is usually where I've found the trouble. Some Van's also have a second sensor, on the radiator, and it too, will cause the fan to stop working.

if you're not sure, spend $25.00 at alldatadiy.com and get the schematics for the Van online. the cooling fan circuit is drawn out for you very simply, and it's not that hard to work on, really!

good luck,
Slantsixness

[Bigjohnjr]

OK I played with it again, when you run the A/C the fan cycles.
I think that is normal.

When the van is just running (no ac) the low speed of the fan does not work at all.

I picked up another fan from a junkie and installed it. Same problem

I looked at the wireing diagram and it the fan has 4 wires.

Black - ground
Dark green - Low speed
Light green - High speed
Yellow - High speed ??? ( not sure about it )

When I put 12 volts on the light green the fan spins.
When I put 12 volts on the dark green I get nothing.
When I put 12 volts on the yellow I get sparks, nothing else.

Could both fans be bad on the low speed?

I also tested the dark green wire and I get 0 volts.

I pulled the purple wire from the temp sensor and shorted it to ground and the temp gauge goes all the way to hot and the check gauges light lights up and still nothing from the fan.

I don't get it..... It is just a simple fan, it is not rocket science.

Please help....

[woscarr]

I had the same problem with the "temp going up real hight in traffic". Put on the 4-ways in the left turning lane..eek!

My problem turned out to be loose connection at the fan. Very carefully (very hot manifold, not mention high speed fan) put my hand down there.. touch the plug fan comes on, let go fan goes off. Wire tie-rap time !

Once in a blue moon I'll have to change the tie-rap... guess I should look into that soon.

My guage always stays just below half, if it moves from there it's time to pop the hood again.

92 voyager se

[slantsixness]

The yellow wire's a trigger, sends a pulse back to tell the computer it's running.
The fan you tested is bad. There are a crapload of bad fans out there. Buy a new replacement one at any cheap auto parts store.