Does anybody know how to find the wiring diagram for a 90 Euro Lumina?
My auxiliary cooling fan wont run unless I pull its control relay and stick a jumper in it's place.
I need to be able to track back to which sensor is responsible to start and stop this fan.

try replacing the relay. if that doesn't work, the motor is probably drawing too many amps for the relay and the motor needs to be replaced

Hi Richtazz, thanks but I've already tried that, the relay works fine for the main fan, and if I just stick a jumper into the sockets where the relay sits (contact side not coil side hehe) the aux fan runs like a charm for hours on end, I drove all through the Okanogan (hot hot hot) in this manner with no trouble, it's just a pain remembering to pull the jumper when I leave the car for a while.
That's why I'm wondering if its not a sensor or something in the computer that's not turning on the relay, oh ya i did take a volt meter and there is no power going to the coil side of the relay.
Thanks for your ideas though.
DF

The secondary cooling fan is designed to come on only if the coolant temp exceeds 230 degrees. unless your car is overheating, the ecm is not sending a signal to turn it on, thus no power at the relay.

should be on with the A/C running though...

Hmm curiouser and curiouser.
So maybe a loose wire from the ECM to the relay coil then, because she sure do overheat without it !
Thats why I'm interested in getting my hands on a wiring diagram, don't want to have to tear every panel off looking for it. Unless the sensor to the ECM is pooched? The dashboard guage still works...

If that's a two-wire to the ECM's temp sensor, the fan should come on if you jump across the plug with the key on.

Not sure what you're saying there Jeff. I dont know what the ECM looks like and I had kind of assumed the sensor was an analog sensor ie ECM sees actual temp via the sensor, not a temp switch. I also dont know where the sensor might be located and being an electrician I'm a little shy about shorting unidentified wires together hehe.

Does anybody know how to find the wiring diagram for a 90 Euro Lumina?
My auxiliary cooling fan wont run unless I pull its control relay and stick a jumper in it's place.
I need to be able to track back to which sensor is responsible to start and stop this fan.
I guess no one knows where to find a wiring diagram for this vehicle?
Oh well.