skl2

Got done with a 25 min drive and parked it...no issues. Started it back up 10 min later and the fan belt warning light came on. The belts are admittedly the only thing I haven't changed since buying the car last year (have done just about everything else!) and I have a spare set of belts in the front trunk. Anyway, checked the belts and they all look fine. Any ideas why the light came on? Should I just go ahead and change them? TIA

FGL28

Cheap insurance. You can even do it yourself.

C2Cab95

Did you check to see if the plastic roller wheel on the sensor broke off? If it did, that could be causing your issue.

http://www.ebay.com/itm/Porsche-964-...#ht_500wt_1081

You can see that plastic wheel that I'm talking about in the ebay listing. It's common for those to fail over time leaving just the metal bearing running on your belt.

jakfrost

Isn't there a micro switch on the idler wheel assy? Could that be the culprit?

Jim

Edward

The sensor does nothing WRT the wear on the belts. It's only there to tell you if it has snapped, warning you of impending doom (no fan blowing to an air cooled engine). Jim is right on: switch went bad in the assembly. I've replaced the sensor before ...easy peezy and fixed my false "light on" warning. That's all you need to do. Now whether your belts need replacing is a wholly different topic.

Edward

C2Cab95

Yes, but if the plastic wheel on the sensor fails, it could result in a false reading.

IXLR8

Disconnect the connector to the sensor and bypass it. If the warning light goes off, then you know it is the sensor.

You can also connect a DMM across the sensor and test it using the continuity feature of the meter.

pp000830

Check the idler wheel on the belt sensor, it is probably broken. If you have the belt replaced by someone else make sure the tool in your car's tool kit used in replacing the belt does not go missing. I keep extra belts in the car just in case of an on the road issue. Your car comes with all the tools needed to replace the two rear facing belts.

pp000830

I really like the seat accessory looking up at the camera!

sds

What specific tool is that? I want to check if i have it...

skl2

I checked that and the plastic roller wheel is fully in tact. Is there also a sensor in there that could have failed but is not noticeable by looking?

Slow Guy

Wheel arm actuates a microswitch, the microswitch itself may be bad. As stated above, easy check with a multimeter.


I am really trying to understand this post...
Ahh OK. Understand it now. I'm a little slow sometimes.

Silver993

I had a similar experience to the OP. Cruising along and the light comes on...heart rate increases...pull over and check. In my case, everything looked fine. That evening, I removed the little sensor and lubricated best I could with some WD-40. Reinstalled and no light since (a few months have passed since then).

You might try the same route, or buy a new one.

John D.

I had exactly the same experience... I also lubed with WD-40 which worked for a while, but - eventually, the bearing started squealing...

Anyway - I had two choices - replace the assembly or bypass the microswitch (a wire crossover into the female harness plug for the switch). I chose the latter..

Anyway - hope this helps..!

John D.

C2Cab95

Me too! So much so in fact that I have another one on order... Just have to wait until January!