Cooling Fan Wring Problem
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Joined: Jun 2008
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From: Norman OK
Cooling Fan Wiring Problem
Help please.. 91 stock L98. Just finished changing both head gaskets due to the infamous #7 cylinder failure - cylinder filled with coolant. While doing post repair runs, I found the cooling fans were not coming on. During troubleshooting I found I had lost switched 12VDC to pin D of each fan relay. Instead of having 12vdc with the ign switch on, I have less than a volt. Jumpering constant (hot) pin E to Pin D at either relay back feeds the wires and fans work normally. So, somewhere during head r&r, I apparently damaged a wire or blew a fuse I can't find. My wiring diagrams are less than stellar. Can anyone tell me exactly what fuse feeds the "ignition on" 12 VDC fan circuit to pin D and/or before I start tearing in to unneeded 20 year old wire bundles to chase wires, what the routing of the pin D wires is? Any help would be appreciated.
Last edited by OkieC4; Apr 9, 2010 at 03:16 PM.
Thread Starter
Instructor
Joined: Jun 2008
Posts: 173
Likes: 0
From: Norman OK
I traced the wiring back to the bulkhead connector. Before I take apart anything else, could anyone with a 91 owners manual check the fuse listings to see which fuse operated the cooling fans? Maybe there is one in the aux fuse panel? I see nothing in the fuse panel that relates to the fans. On the 93 and up, there is a fuse in the main panel marked "fan".
