I am putting my '70 240 back together and I can't figure out the fan blower switch sub-harness wiring. I know where each of the three plugs go, but where do the red, blue and black individual wires go? The red is hot as soon as the ignition is "on." The blue and black go hot when I turn the blower switch on.

First, a suggestion: download the 1971 Chassis Supplement from XenonS30, unless you already have a copy of the 70 FSM. The wiring is close enough for me to piece things together.

The blue wire is identitified in Fig VI-1 as the Blower Motor Power Source (#34). I assume the black wire is the ground, seeing that it has a ring lug on it. It probably mounts to the motor housing.

It would help if you would identify the wire colors of all the wires on the connectors. That way they can be better matched to the descriptions in the supplement.

Good suggestion on downloading the FSM Supplement, it is very detailed in this area.

On my dash (now out of the car) the black is a ground as Steve says. It is attached to a bolt on the rearmost left bracket of the center dash right above where it mounts to the tunnel. The red wire is the blower power and is attached to a similar gauge blue wire in one of the two bundles on the right side of the center dash. Finally, the FSM supplement says the blue wire is the A/C power where so equipped, and I agree. Mine went to the A/C on/off switch, is now stubbed off since I have pulled the A/C.

Jim

A bit more detail: when you get the FSM Supplement, on page 27 see that item 55 connects to item 34. Item 54 is an orphan if you don't have A/C.

Jim