Thread: Early Heater Box Wiring Question

Hi everyone,

I’ve recently overhauled the heater box out of my 1979. When I got the car, the heater box had no wiring connected to it.
I’ve since tested it and all works well on both fan speeds. I’ve also tracked down the brown and white wire that feeds it from the ignition key.
On the wiring diagram it shows an inline fuse. Does anyone know what size?
Secondly, the diagram just shows the positive and negative to the box, but I’m not sure if the resistor is on the negative side of the motor in the circuit or the positive? Can anyone help with that one?
Thanks,
Marcus

Ok…I’m going to answer my own question after looking at Series 3 wiring which look to have the same motor and resistor.
Power comes in to the switch (brown/white) which has an inline fuse (25a). Then from the hi and low speeds of the switch to the resistor. Comes out of the resistor to one side of the motor. Other side of the motor is connected to ground.