Anyone have a good write-up, or have any tips on how to replace the Fan Temp Switch in the radiator? Is there only 1? Are there 2 of them; one for each fan? I've done a search here and have only found a small ETKA image of where it's actually located. I checked the TT FAQ, but found nothing. Checked the tech articles and only found the B5 S4 version. Appreciate any help you can provide. My car is running too hot, and I'd rather not take it to the dealer (they were asking $1300 for labor and parts...just for the thermostat replacement!)

A little background if you care to read more:

My car has been overheating both on idle and when driving around (especially with the warmer outside temps). Both fans turn on when the A/C is switched on; with the A/C off, both fans kick in only when the coolant/water temp gauge reads "H". Plus, when I'm approaching "H", a fan (maybe both) makes a "clicking" noise, then turns on for a second or two, "click" again, then stops. A few seconds later, it does the same thing - "click", turn on for a couple seconds, "click" again then stops. After another cycle or two of this weird behavior (maybe it's normal?), the fans finally come on and remain on, thus cooling the system and bringing the temp gauge back to center. I double-checked the actual coolant temp and it fluctuates in relation to this --> goes all the way up to 121 degrees (not good!), then back down again (around 87-90 degrees) once the fans finally stay on.

Also, I recently had the timing belt service done and the shop replaced the water pump with the metal impeller version, as well as put in the Whaler thermostat. Over this past weekend, I replaced the Whaler thermostat with an OEM version (THANKS to those here who suggested I replace the Whaler version with OEM - and a huge THANKS to RafaTT for a great write-up...it wasn't hard at all to do). Coolant temp sensor has been replaced multiple times already, so it's not that. All the fuses are good as well. G12 coolant (reddish-pink) is in the resevoir. All this work, and I'm still overheating. This problem started right before Fall/Winter of '05, then it got cold outside so the problem didn't happen during the next few months. Once the outside temps started reaching above 50/60+ degrees, the issue returned. I was hoping that the timing belt/water pump service would resolve the issue (plus putting in a new OEM T-Stat), but it didn't.

Thanks in advance and thanks for reading my long post! Hopefully, replacing the switch is a relatively "simple" job (like the thermostat!). I would like to do this first before I get into replacing the more expensive parts.

Chris

 

Does it overheat with the AC on? I didn't catch that from your description

 

that you can get at germanautoparts.com. It is under VW(do a search, this was discussed before). It is very simple to replace but it is a royal PITA to get to the part. I did replace that one on my car working from both top and bottom of the car, removing the battery tray gives some clearance for the wiring, work the switch from below. It is located on the radiator left tank (driver side), close to the bottom. You will need a deep socket (I don't remember the size) and a cold car. Just pull the electric connector, put the socket and replace the part. There will be little to none coolant lost if car is cold. email me if you want pics of the part and other details.

 

and purchased the low temp version yesterday from germanautoparts.com. From your description, I think I can manage, but I'll definitely hit you up on email if necessary. Thanks again!

 

...than normal, but rarely gets to "H". So, it helps a bit, but I'd hate to do that all the time when my car overheats.

 

you will not get the big pics, but this will help.<ul><li><a href="http://www.loomknitting.com/auditt/radiatorswitch/107453823.html">Vehicles With A/C Pressure Switch - F129 -</a></li></ul>

 

<ul><li><a href="http://www.loomknitting.com/auditt/radiatorswitch/107453825.html">Vehicles With High Pressure Sensor - G65 -</a></li></ul>

 

the fan switches, and you will still overheat.

What do you mean it runs hotter? Where on the gauge? about 5/8? 1/4? 7/8?

Is the temp normal when you are cruising in the freeway with AC off?

 

When it's at "H", and I turn on the A/C, then the gauge goes down 1 tick or so (around 115 degrees).

If I keep the A/C on at all times, the gauge still goes up (2 ticks or a bit more), but almost never goes to "H" (can't remember a time).

Appreciate the responses though. I'll take any suggestions at this point.

 

I believe I've noticed a few posts of yours in the past (using the search) regarding this issue (I think it was you). Unfortunately, the image or link you posted in that old post was dead - so I kept searching for help.

Thank you again!