Hello all, restoring a 92 rs tbi and I'm having the strangest problem with the cooling fan and it all comes back to the relay.
bought a new connector and a New relay, (old was burnt out) spliced and heat shrinked the new connector in properly, in my wiring diagrams (which I have seen this happen before and done it myself) shows that my heater and ac controls (when ignition is in acc) and or cooling fan switch (obviously when hot enough) flip my relay to turn my fan on, every time I have my ac controls on something other than off (I keep it on normal) my coolant fan is supposed to turn on when I hit acc but it doesnt. I've taken the relay off and tested it and it's a brand new relay, I've swapped it with the relay next to it and I feel it click on everytime I hit acc while it's connected to that other circuit. I've taken the relay connector and completed the circuit with a simple 12 awg piece of wire, and the fans come on! So obviously the problem seems to be my relay...but it's a brand new relay! And tested as such! I'm stumped I theorize that my relay isn't getting enough power to switch?? I'm kind of new to electrical so I'm gonna ask is that possible? If not...what seems to be the problem??

 

Double check to make sure your wires are actually making contact with the relay. On my car, when I put my new relay in, the wires pushed back in the connector and lost connectivity with the relay causing me headaches. Also realize that sometimes you get a bad relay when you buy a new one. It's electronics, it happens sometimes.