944 radiator fuse pops

Kiba · 02:42 PM

I have an 84 944. I have also looked over various threads and I was unable to find anything having to do with this issue.

The problem- The cooling fans will not come on. I replaced the 16amp fuse. When the engine reached the correct operating temp, I heard a pop and the engine continued to get hotter. I shut off the car and checked the fuse and found that it had blown. Now the fans used to work last summer, but for whatever reason now the fuse pops. I just make sure I don't let the car idle long. If I keep moving it stays cool. However I live in AZ and summer is fast approaching and I would like to resolve this issue soon. Any help concerning this matter would be of great help. Thank you in advance.

Oh and its the 16amp fuse in slot 3 on the top. And if the cooling relay is bad will it cause this?

matthewb · 04-07-2010, 04:18 PM

Did you check to make sure that your fans are able to spin? The bearings could have frozen up and in a lock motor situation maybe it is pulling to much current.

smokin_944 · smokin_944's Garage

+1 matthewb. On the early cars IIRC, the fuses for the fans are in the secondary fuse box, slot 3 is main/driver side fan, and slot 5 is compressor/passenger side fan. Check both fans with a power source (12 volt) to make sure they aren't seized. Once you've established the status of the fans, I would suggest Clark's garage. They have a detailed troubleshooting guide for early cars.

mattdavis11 · 04-08-2010, 06:49 AM

I'd jump the thermo fan switch on the rad and see if the fuse pops. They should come on instantly when jumped. A paper clip works as a great jumper when you unplug the leads. Check your grounds too. They are right behind the headlight, near the a/c drier.

Kiba · 04-08-2010, 12:54 PM

Thanks, I'll check the ground. I don't think it's the thermo switch as when this goes bad the fans both kick on and will not shut off in most cases. I also don't believe that both fans have froze up due to the fact that they both ran fine last summer. I looked over the relay and did not see any visual signs of defects but I'm not an expert in these. I'm hoping that it is not a short in a wire somewhere. That would explain the fuse popping.

Thanks again.

pinball_0 · 04-08-2010, 01:06 PM

when my thermo switch on mine failed - early 85 944,the switch was open and not connecting when radiator heat was hot... no fans and caused oil cooler fail. The poping fuse is probably bad fan motor or relay