thanks Jim Gives me somethings to check and yes there is power to the fuse clips
can you tell me is there any harm in running a wire from the fuse block to the Switch ? thanks Again
I've just heard of issues with the clip that has power from the ignition switch being a good connection to the one end of the fuse and then at the other cap end on the fuse it would have power but then have a poor connection between that end and the fuse clip that would then go out to the circuit, in your case the blower switch.
If you do not want to find the real reason of your issue is then yes you could run a new wire from the fuse block to the switch but you might want to dig into your problem some more as this bypass or rerouting will require some specialized parts.
Looking at a wiring diagram for a 69, the heater fuse is only protecting that circuit and is not tied directly into anything else. There is a terminal in the fuse box labeled ACC and this supplies power just like it would with the different ignition key positions as what is happening with the heater circuit but it is on a different leg off of the fuse block and I would be hesitant of using that ACC terminal to then power the blower switch.
How I would probably do a bypass would be to get one of glass fuse taps that clips onto the fused end of the heater fuse and fuse block clip and then leave you with a 1/4" male terminal. Since this clip will fit either end of the fuse in the fuse block you MUST use the proper side that is protected by the fuse. If you do not, then if a short occurs then things will not be good and then will have a possible electrical fire.
You then need to get a 1/4" insulated female terminal to go onto the 1/4" male glass fuse tap clip and then crimp on a section of 14 gauge wire that will reach the blower switch and it's plug. I would then extract the factory brown wire and terminal out of the housing with the other wires and then buy a new terminal end that would go into that plug and lock in like factory. With the raw terminal end on the brown wire you will no longer be using is to slide over some heat shrink tubing over the exposed end so it cannot short to ground and then cable tie it back in the harness to secure it down.
Glass fuse tap I would use:
Glass fuse tap that would work BUT has less surface contact area:
I don't have a link or picture of the terminal end for in the switch end but it probably is a standard Packard type of connector.
If you do this bypass properly, you can easily remove this modification and the new wire as well as the wired past it will be protected like factory with the fuse in the fuse block.