clancy

My 2001 A6 2.7 stays at the mid point on the water temp gauge except during a long climb at elevation (5000+ ft) with the AC engaged on hot days (80+ degrees F).

Is there an easy way to test to see if all cooling fans and switches/relays/clutch are working correctly? All 3 fans run when the AC is engaged at idle. But I don't know if they kick up to high speed when climbing a long hill at 65mph. I want to rule this out before I start to work on other possible causes.

Thanks

Airbag

hmmm.. well i guess i have a bad one if this is the case ..my electric one doesnt seem to come on at all ...

clancy

Am I to gather this means there is no simple way to verify both speeds on both electric fans are functional other than manually jumping the connector with a feed directly from the battery? I did find on the technical articles that I can also jump the pins on the coolant fan control thermal switch on the lower radiator hose. This will prove both fans work at both speeds. But this does not tell me whether the switch is functional or whether the cooling circuit is working correctly.

I was hoping that VCDS or something would provide a diagnostic that said the thermal switch was not functioning or that the fans were operating properly. Oh well.

Any thoughts as to why my car begins to overheat on long climbs at elevation with the AC engaged on hot days? No problems on hot days in stop and go traffic with AC on. The problem existed before and after doing a timing belt, thermostat, etc. Radiators look clean. Wouldn't stop and go traffic be a tougher demand than 65 MPH up a hill?