Carpokes Porsche Forum

Hello all, my first official post! first off thanks for allowing me to join and be a part of this fine group!

Ok so down to the question and don't hate on me too much as I have read many many cooling posts and don't seem to find the answer to the question I am looking for if there is one. I picked up a sorely neglected 87 924S with a leaking water pump. After tearing into the front of the motor and finding the T-Belt waaaaay too tight and a destroyed water pump I have it all back together now and running very well. I noticed that my cooling fan comes on immediately when the key is switched on. I tore into the relays and right away noticed someone has wired a second relay into the cooling fan relay. My question is.... was this a known fix for cooling fan issues or did someone rig up a quick fix??? any help or insight is greatly appreciated. Ed

If it's an obvious after-market relay wired into the cooling fan circuit, then it sounds to me like someone gave up diagnosing a problem and tried to use brute force instead. Can't say I've ever heard of anyone else doing that based on decades of 944 Internetting -- as best I know that's a known fix for cooling fan issues (and even if it were, the system works fine as designed by the factory, assuming everything is working right).

Hi there! Your question is not one I can answer but someone here will know and/or will have thoughts concerning your question.

Meanwhile, welcome to Carpokes! Glad you found the site and thank you for joining up! I'll keep an eye on your thread and try to help find someone who might have some insight on the anomaly.

If it's an obvious after-market relay wired into the cooling fan circuit, then it sounds to me like someone gave up diagnosing a problem and tried to use brute force instead. Can't say I've ever heard of anyone else doing that based on decades of 944 Internetting -- as best I know that's a known fix for cooling fan issues (and even if it were, the system works fine as designed by the factory, assuming everything is working right).

thanks for the response, yes it looks like a monkey wired it in there. It even has a regular wire nut you would use in residential home wiring. I guess that should have been a huge clue that it wasn't a known way to fix the cooling fans system. I am going to remove it and wire the old relay back up and see what I can find out.

I'd guess that monkey-wiring was put there for a reason. It's probable that the fan circuits weren't working correctly before that was done either, so it may just be masking a downstream problem. I highly recommend the Focus9 solid state fan relay with the diagnostics. It's really nice as a relay, but it will give you much more ability to _see_ when the low- and high-speed fan circuits are being called for and also just to test each downstream circuit with the press of a button. I think it's a fair guess that you'll have more troubleshooting to do once you replace the bad relay, so this will be very worth it.
-Neil

Ugh. The Focus9 solid state relay is for later 944's. I have an 83 and 84. Would love a permanent solution.

If the car has A/C, then the double relays are very expensive. Perhaps one side failed, the owner was cheap, and this is an external workaround for that part of the relay.

So to update....The added relay was wired to the high speed fan. I removed it and hooked it back up the way it came from the factory and everything is working fine. The high speed fan kicks on when its supposed to. I really don't have an answer as to why the extra relay was added. I replaced the radiator fan switch when I did the waterpump, belts and front seals. maybe it was bad, idk but everything is working correctly now.

Hoosier924S wrote: Thu Sep 28, 2023 5:05 pm So to update....The added relay was wired to the high speed fan. I removed it and hooked it back up the way it came from the factory and everything is working fine. The high speed fan kicks on when its supposed to. I really don't have an answer as to why the extra relay was added. I replaced the radiator fan switch when I did the waterpump, belts and front seals. maybe it was bad, idk but everything is working correctly now.

Relays can be funny things too -- sometimes working and sometimes getting stuck. Time will tell if that was the issue the PO was trying to bypass....