Overheating circles

[CASTAMILE]

Ok I need some help, I have been searching and reading all the info I can about fan modules, fuses, antifreeze tank and so on. I have taken the bug to the shop and had the antifreeze tank and the plastic neck of the radiator hose replaced, at the time the fans were working with the ac on but not with the ac off, so I had it replaced, got halfway home and the red light starts flashing again. Stopped and looked at the fans and neither one works. I am tied of taking it to the mechanic for him to guess what is wrong and charge me $200 and it is still not fixed. Can anyone tell me what I can check to see what would keep the fans from coming on? I have checked all the fuses, 5,16, 25 and the ones above the battery all are good. have checked the fans by hooking them to 12 volts directly and both work. I have to be missing something just don't know what it is. Thus I am going in circles

[doublebarrel]

My guise would be the fan control module.It is located under the battery tray on the drivers side.I'm not sure how to check it but if you have checked the fans and they work then I would try this next.You may want to go to www.tdiclub.com,there is a list of trusted tdi mechanics,find one in your area and you will be better off than taking it to them than anyone else.

[CASTAMILE]

Fan module was changed same day that I was coming home and red light started flashing. when I picked it up both fans were working. Thanks for the reply

[DZLBUG]

There is a thermoswitch in the radiator which tells the fans to come on...sounds like yours needs replacing?

Do the fans run now with the A/C engaged?

There is a lot of good fan troubleshooting info over on TDIclub, I have posted links to it in other threads here if you search my posts. Sorry I'm too lazy to do it right now, I just got out of the hospital.

[CASTAMILE]

The fans did work when the ac was on but the mechanic told me that the module needed to be changed becuase they did not come on while the engin was running. So had him install new one and fans worked ok till I got about 15 miles down the road then the red light started flashing and the ac quit working. Lokked at the fans and they were not working. Go figure

[Smileybug]

The fans don't come on all the time when the engine is running.

How many miles on the car? Water pump/timing belt been replaced yet? Are you losing coolant?

[CASTAMILE]

yes to all of the above and 166m miles on the bug. took it to the mechanic again today and he made the fans come on manually and tried to bypass the thermal sensor but the sensor was not getting any juice so he said the new module is bad and had to order a new one but i don't know if he is right

[Smileybug]

So you are losing coolant? When was the water pump replaced last?

Certainly could be a fan problem too. But if you are losing coolant, I would suspect other problems as well.

[VW_Factor]

If the fans run with the AC turned on, the module is ok. (as far as I understand, I went through the same thing, except I was the mechanic).

If they dont come on by themselves when the water is warm, its likely the temp switch in the radiator. Bottom, driver side. Has three prongs. You can jumper the connector part (car side) and enable the fans, either low or high. You should do this to verify that both fans are still good. (1 of mine turned out to be bad).

I didnt take the time to verify the switch or anything, so I just replaced it.

I went through this process following directions I read here on these forums. The directions are easy to follow and straight forward.

[CASTAMILE]

Ok went and got the new module from the Mechanic becuase it was taking him to long to get to it. I put the new module in and nothing happens no fan with or with out ac and now the ac compressor does not come on at all. the module can not be that technical, 2 plugs and bolt it on?
I saw the mechanic jumper some wires together to make the compressor kick in the other day so I know it was working. Checked fuses again and found nothing wrong. OK somebody give me a hand. Tired of paying $100 here and there. I have to be missing something.

[Minklsteiner]

I have seen many bad engine coolant temp sensors cause the light to come on and blink, even with the car not actually overheating. Is yours green or black, if it is black start there. It is located on the right side of the block. Has the check engine light been on? Has the blue coolant light ever stayed on? Do you have any DTC's showing up?

Have you verified that the car is actually over heating, you could do this by measuring the temp of the hoses. This will also help you see if the thermostat is opening, because if it is not the hose coming out of the thermostat houseing will be cooler than the others.

With that many miles water pump might be broken/cracked especially if it has the plastic impellar