The fan on my brothers 87 grand national does not turn on. I have checked the fuse under the dash. I also checked the relays by grounding the green wire by the intake I can hear them click but the fan won’t turn on. I have tried to put power directly to the fan and the fan will turn on but only when plugged in one way. I don’t know what to check next. Any help would be appreciated. Is the fan toast? Thanks
GN cooling fan won’t turn on
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Sounds like the relay is toast; jump a wire across the terminals. See if that does it.
Thanks. I will try that in a few hrs. There are two should both trigger them on separately? Or do they work together?
One is the feed and the other is the load. A quick explanation of a standard automotive relay: 2 pins- (85 & 86) are the coil aka the "light" side. One goes to ground, one goes to hot, and they throw the "heavy" side aka the switch (normally open 30 & 87, normally closed 87a & 87, 30 is normally the feed).
So, if you can't trigger a relay on the light/coil side, jumper across the heavy/switch side to eliminate it as part of the troubleshooting process. If your desired accessory works while jumped out, start looking at the relay itself or the trigger side.
You said grounding the green wire wouldn't kick it on, so you need to verify voltage on the other side of the coil to rule out the light/coil side.
So, if you can't trigger a relay on the light/coil side, jumper across the heavy/switch side to eliminate it as part of the troubleshooting process. If your desired accessory works while jumped out, start looking at the relay itself or the trigger side.
You said grounding the green wire wouldn't kick it on, so you need to verify voltage on the other side of the coil to rule out the light/coil side.
I have read that problem cannot be repaired on a GN and to help your brother out you should give him a few hundred to take the problem off his hands... 
I did offer a few hundred but he said no 😔. If I fix it I get to drive it. So that's a win.
I tried bypassing both of the relays fan doesn't kick on. It also seems that when grounding the green wire under the intake only one relay clicks. I tried swapping them and only one clicks when grounding the green wire. Any other suggestions? Thanks
I tried bypassing both of the relays fan doesn't kick on. It also seems that when grounding the green wire under the intake only one relay clicks. I tried swapping them and only one clicks when grounding the green wire. Any other suggestions? Thanks
Basic electrical trouble shooting is next. I'd say you have an open in the circuit after the relay from the symptoms described. Have you checked the fan grounding point?
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