93 Na weird wiring gremlin
 

The cooling fan on my non air conditioned 93 NA does not want to turn on. I bench tested it with a 12v battery and confirmed it is working, I bypassed the cooling fan relay and jumped the ground and TSA on the diagnostic to skip the coolant temp sensor and the fan still doesn't turn on. The fuze looks good.

This is related to another wiring issue I am having. The left pop up doesn't go up or down, the other side works, and I know its not the headlight motor itself.

When I have the cooling fan relay in place and I jump tsa/ ground, the cooling fan relay makes a continuous buzzing sound only when I plug in the pop up headlight motor...

somewhere there must be wires touching each other but the wiring harness looks perfectly fine... where do I start looking for this?

If you're referring to the passenger side fan on a US car, I had the same issue. I don't know what the official fix is but I ended up splicing the fan wires across to the other so it would turn on with the temp sensor switch.

https://cimg6.ibsrv.net/gimg/www.mia...4633a56575.png
12v to 12v and ground to ground if I remember correctly. It was incredibly simple and I have had any issues for 2 years now.

I may be totally wrong on the issue you're having but this is how I read it.