'89 Firebird cooling fans not working

[87bluebird]

The secondary fan (the one that comes on with A/C pressure and/or very high temp) had a problem with it's temp sensor, so I've got it wired to a switch. The only time I use the car is for SCCA events, so when I'm racing I turn that fan on all the time. The last SCCA event, they were both working at the start of the day. Later on, they both quit - even the one that is hard wired.

Now, neither fan will come on now, so I'm thinking that there is a common source for power for the two fans and that the problem is in the power circuit for the fans. Is it true that they have the same power source - even though they have two separate circuits for actuating them? I've checked all of my fuses and they're all fine.

Any ideas? If anyone knows the wiring scheme (wire colors) so that I can try to trace the power wires, that would be of great help, too.

Thanks,
Getting hot in AL

[87bluebird]

Well, both fans are working now. I discovered that they don't share an immediate power source. There are two different relays that act on the power circuit for each of the fans. The fans do share a common ground near those two relays - at the front passenger corner of the engine compartment on the radiator support. The relays are in that corner of the engine compartment as well. There is a larger orange wire feeding both relays that must be the power from the fuse box. When I first checked these orange wires (which should have constant power with the key on), neither of them had that constant power. I removed each of the fuses in order to visually check them and also double check them with a meter. Turns out after the fuse check, the fans started working. It must have been a bit of corrosion at the fuse connection??

Whatever the problem, they are working properly now and I can go racing. I also know a little bit more about the power circuit than I did.

Peace and good luck to all!

Cooling off in AL