radiator fan inop , blown coolant resevoir = frustrated audi owner

[Huw Powell]

> car: 88 90q
> symptom:  radiator fan will not come on
>
> So far, I have tried jumping the fan switch wires to rule out the sender
> which resulted in audible clicking of the fan relay but no movement in
> the fan. Next I disconnected the harness from the fan and hooked up my
> DMM to the connector, which showed no power through the wiring when
> jumping the connector.  Next I checked the two fuses that relate to the
> cooling fan:  both were fine.

As I recall, my 90Q has some sort of resistor pack or something in the
wiring on the way to the fan - mounted to the fan shroud.  You could
check whatever that is.

You could measure the resistance (continuity) from the relay output to
the fan "hot" terminal; likewise the fan ground wire.

And, make sure that relay is actually working and passing along current,
not just clicking...

--
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/