Fan switch on a avu engine?

[simonglos]

Does any one know where the fan switch is on the avu engine. There seems to a sensor on the bottom of the radiator but it only has two prongs coming out of it, shouldn't the switch have 4?

[simonglos]

The only reason why I am asking is the fan isn't cutting in, usually when you bridge the wires the fan should cut in but nothing has happened?

[Umai Naa!!]

There's a fan module under the left side chassis rail.

Also try running the fan directly off the battery to test. They are known to fail as well.

[JustCruisn]

Everything you need to know here http://pics.tdiclub.com/data/516/A4_...ting_Rev_7.pdf

[simonglos]

Ok I have Actually run power from the battery to the fans and they both powered up, and when I turn on the a/c the fans start spinning. I thought the switch might of been in a different place maybe they only have one speed on the avu engine judging by only two pins. Maybe the module is playing up. Because as I have found from other vehicles if you bridge the plug the fans usually come on, but not in this case.

[Umai Naa!!]

Not 100% clear what car this is, buy if it has the fuse box on top of the battery, check for continuity. They're known to break internally, and one of the fuses is for the fan module.

[simonglos]

Thanks for the replys. It's a 3dr mk4 golf with a 1.6avu engine. I will check the resistance in the wirring tomorrow. Are the modules common to play up at all?

[Umai Naa!!]

Yeah, they do crack it from time to time. Particularly if the car had some frontal accident history, or has been aubmersed in the drink in that area of the car.

[simonglos]

Here we go this is a picture of the fan switch and conection just checking the resistance in the wires now.

[simonglos]

By the looks of things that wire is heading up towards the Ecu. Do you recon Iam looking at the wrong switch?

[simonglos]

This looks the like the switch which usually goes in the radiator?

[JustCruisn]

The radiator thermo switch is quite large and is triangular at bottom of radiator, 3 large pins. The 1st pic, yellow, looks like a temp sensor small current device not for switching large loads like a fan.
Last pic looks like the coolant junction at the side of the engine it has a coolant temp sensor also.

[JustCruisn]

Hang on a sec. A 3 door golf hey, is this a UK import?

[simonglos]

It's australian delivered, a bit of a rare find. This is what is throwing me out, I might phone up vw today and see if I can get some wirring diagrams. Isn't this usually where than fan switch goes, just above the bottom hose?