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**VetteVet** · 03-08-2015, 12:18 AM

[QUOTE=lasmith03;7080434]I've got a non-AC 69 C-10. My heater isn't working.

My heater switch harness looks like this (pic from another post on this board):

But the brown wire that is shown in the wiring diagram on this board running from the back of the fuse panel to this harness at the heater switch does not do so on my truck. The brown wire instead goes to the ignition switch. (see the attached pic at the bottom...its the bottom wire in the pic below the two tan ones. BTW None of the wires are cut. I just wrapped them where the previous owner had shaved off the covering to test them.) I'm positive it is this wire. I stripped off all the wrapping and ran it back to the fusebox with it removed from the firewall.

Do I need to pull this brown wire out of the ignition switch plug and plug it into the empty 4th spot on the heater plug at the switch?

Thanks for your help.

The brown wire you are seeing is the key switch accessory wire and it is a 12 gauge wire from the key switch shown in the first diagram below. It feeds the wipers the heater and the turn signal flashers. It is indicated by the first arrow on the left.

Locate the heater switch on the diagram and you'll see another brown wire that is the feed wire to the switch. It is a 14 gauge wire and it comes from the heater fuse on the fuse panel up to the switch. You will have to run a new wire in place of it. You can't pull the other wire out of the key switch or you won't have any power for the accessories or the heater switch.

look at the fuse panel in the first diagram and you will see both brown wires on the left end of the panel.

If you match the left side of the top diagram with the right side of bottom diagram visually, you can see how the wires match up and where they go.

03-08-2015, 12:18 AM	#4
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,703	Re: 69 C10 Heater Wiring [QUOTE=lasmith03;7080434]I've got a non-AC 69 C-10. My heater isn't working. My heater switch harness looks like this (pic from another post on this board): But the brown wire that is shown in the wiring diagram on this board running from the back of the fuse panel to this harness at the heater switch does not do so on my truck. The brown wire instead goes to the ignition switch. (see the attached pic at the bottom...its the bottom wire in the pic below the two tan ones. BTW None of the wires are cut. I just wrapped them where the previous owner had shaved off the covering to test them.) I'm positive it is this wire. I stripped off all the wrapping and ran it back to the fusebox with it removed from the firewall. Do I need to pull this brown wire out of the ignition switch plug and plug it into the empty 4th spot on the heater plug at the switch? Thanks for your help. The brown wire you are seeing is the key switch accessory wire and it is a 12 gauge wire from the key switch shown in the first diagram below. It feeds the wipers the heater and the turn signal flashers. It is indicated by the first arrow on the left. Locate the heater switch on the diagram and you'll see another brown wire that is the feed wire to the switch. It is a 14 gauge wire and it comes from the heater fuse on the fuse panel up to the switch. You will have to run a new wire in place of it. You can't pull the other wire out of the key switch or you won't have any power for the accessories or the heater switch. look at the fuse panel in the first diagram and you will see both brown wires on the left end of the panel. If you match the left side of the top diagram with the right side of bottom diagram visually, you can see how the wires match up and where they go. __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative.