Hey all, whats up!

We've had a baaad summer over here this year, so I've only driven the Camaro a handful times. Last time I drove it some weeks back, it overheated as the fan had stopped running.

Today I finally had some time and weather to do some troubleshooting. I followed the wires from the fan to the relay near the battery. This relay was not engaging with the car running and the A/C wire (on the pass. side frame rail) unplugged. It should. So I tried shortcutting the wires (fat orange to fat black going to the fan), and nothing.
Then I put the volt meter on the fat orange wire and found only ~5 volts I am assuming this should be 12v, right ?

So, where does this fat orange wire go? I seemed to recall from before that the middle relay on the firewall near the brake booster is also related to the fan, is that correct? I also unplugged this relay and checked the fat orange wires there and one of them was just 5v there as well? WTF?

If anyone has any input on where to troubleshoot from here, Im all ears!

Thanks!


Ken

 

There should definitely be 12V on the orange wire.. It supplies the main juice to run the fan(s)

Since you have a TPI car with AC, I'll assume you have two fans.. FWIW, Below is the schematic diagram for the dual fan system. You can see the orange wire marked "440 ORN").

Even if you have only one fan, the orange wire should still be 12 Volts.

I would disconnect the battery and use an Ohm meter to measure beween the positive battery terminal and the orange wire. There should be very little resistance.

 

Hey Jim,

Thanks for your suggestion and confirmation on the voltage. That's what I thought as it wouldn't make any sense to not use 12volts for something as power demanding as a large fan. Just had to check since it was exactly 5volts and since Im aware that is a voltage level found elsewhere on these engines

Anyway, I will check the resistance when I come home from work and let you know what I find. BTW, my car has the single fan.

Any idea of the physical routing of this cable? It seems pretty obvious that Im looking at a bad connection somewhere.
Oh, and also - is the relay in the middle of the 3 on the firewall related to the fan, or is that just my bad memory slapping me in the face again


Thanks again!


Ken

 

Sorry, I don't know where the orange wire is routed. I don't have a diagram that shows this. The diagram I attached above states "TO BATTERY", but I imagine it passes through the fuse panel along the way.

I can't tell you offhand which relay is the main fan relay on your firewall... My car has two fan relays (one for each fan) and the fuel pump relay on the firewall. FWIW, in my car, the middle relay is the main fan relay.

 

Main power for the fan should come either directly thru a fusible link at the positive battery terminal or thru a fusible link from the positive connection to the starter.

To check that you've got the correct relay, do a continuity check between the power lead at the fan and the pigtail at the relay. Just make sure you're not inadvertently checking 'ground to ground'.

Middle relay near brake booster should be it, although I've heard some claim this relay ran their fuel pump. Either way a continuity check to the fan power (or temp switch) will erase all doubt.

 

Hey guys!

Well, Im pretty confident I stumbled upon the cause of the problem! I ohm'ed the wire between from the relay connector near the radiator and the main positive cable from the batter (disconnected) and sure enough it read around 5 meg..!

So, I started looking at the wiring near the battery, starting with the fuse hanging on the inner fender by the battery as it had a fat orange wire coming out. The fuse and wiring looked fine.
However, on the frame rail right by the battery there are two "snap connectors" - one going up to the mentioned fuse holder. This one was fine, but the other one went into a short wire loom and hooked directly on to the factory wire between the alternator and the battery. I happend to pull a little on this connector to look at it inside the short wire loom, and it was burned to hell!! The insulation was fried and the wire itself was so fragile that when I touched it, it snapped. So obviously this was where the great resistance came from!

I'll replace this piece of wire with one including a fuse holder to prevent this from happening again

Will let you know if this solves the problem!

Attached is a pic of the fried connector/wire.



Ken