69 C10 Heater Wiring

[lasmith03]

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. Here's the wiring diagrams.


http://farm4.static.flickr.com/3645/...c2a8064d_o.jpg

http://farm4.static.flickr.com/3571/...59575fe1_o.jpg