only one fan

[crown220]

i have a 2000 beetle and have the red flashing temp light for a couple days goes then comes.....had the water pump timing belt, redone, was told by mechanic that only high temp fan comes on, what can cause the lower fan not to work? oh yeak also temp sensor was replaced. please help as this is getting anoying. thanks

[marvins_dad]

Summer's coming/is here - check your fans!

My Fan Control Module isn't sending a signal to my low fans, but I don't have overheating issues. We did have the thermostat changed out and currently I don't have low fans...but both fans are running on high.

The link I posted gives you a link to the TDI Club's fan thread - follow those instructions and you can test your fans for high resistance to see if the fans themselves are operating at too high of a resistance to come on OR if the FCM is actually sending the signal to the fans.

It is possible that the fans could have had their low settings burn out at the same time...or really at different times, but you are just now noticing that both are not working in low mode.

Go through that checklist or have your mechanic do so.

[simonsi]

Originally Posted by crown220

i have a 2000 beetle and have the red flashing temp light for a couple days goes then comes.....had the water pump timing belt, redone, was told by mechanic that only high temp fan comes on, what can cause the lower fan not to work? oh yeak also temp sensor was replaced. please help as this is getting anoying. thanks

The fans always run together, they have high and low speeds but always both run at the same speed.

The fans motors are just motors, if one doesn't run because it is burnt out it won't run at all.

Normally if one doesn't run it is that fan motor, if both don't run it is a problem with the Fan Control Module, radiator thermal switch or wiring.

Some cars have a 3rd fan speed, this is controlled by a seperate thermal switch and relay, again it runs both fans, and will work even if you have a defective Fan Control Module killing the other two speeds.