Fix for a 4-button climate switch

You can apply full 12 V to the fan without hurting it. That is what happen on the "high" setting (or with the relay I added). On both my 65 Dart and 65 Newport, there are two wires to the fan - blk = ground, dk grn = positive, as in drawings above. Just find a decent source of 12 V under the dash and jumper it to the dk grn wire and connect the ground. If your fan doesn't turn it is either burned out or the wheel is jammed (which will soon burn it up with power applied). A multi-meter would help verify you are applying 12 V and to measure the current draw.

On my Newport the dk grn wire is a single spade connector that loops over the heater box and connects to a single spade on the resistor pack on the front of the box. I know because I just put the box back in today after replacing the heater core (fogging the windows, then drenched the carpet). On my Dart the heater box is currently out. I looked at it but the dk grn wire is currently dis-connected, but it has the same single space female connector, so I assume it goes to the front of the box also. I will need to replace it since a P.O. did a klutz fix with yellow wire and butt crimps. The original wire is hard and brittle.