Heater wiring question

Trying to get the heater motor working on my series 1.5 and the 2 wires that connect to the resistor are connected but there’s 2 white wires that are at the bottom of the motor and one is not connected. When I look up wiring diagrams it only shows 2 wires going to the heater motor, a green/blue and a green/yellow that connect to the resistor. Where do these white wires connect to? What am I going wrong/not seeing here?

Hi John,

That appears to be not the factory motor, and that’s not surprising given that installing a better blower motor is an easy and popular upgrade. From the photo it also appears that someone has spliced in new wiring, so the white wires will not match your wiring diagram. Perhaps others who have done this upgrade might recognize that motor and chime in as regards the additional white wires from the motor.

Best of luck,

I’m guessing that the white wires are extensions that a PO added to the original Green/Blue and Green/Yellow wires when they fitted the non-original motor. It appears from your photo that is the case, with one of the wires (the top one) spliced to a Green/Blue wire. The extended G/U and G/Y wires should go to each end of the resistor. One of the wires to the motor should be attached to the same end of the resistor as the extended Green/Yellow Wire. The second wire to the motor should be grounded to the body or any other convenient Black (Ground) wire.

It’s a mess. You have a motor from a different application. It’s not clear from your photos and description how that motor is intended to be used or how the wiring is connected. So lets start from start and please describe:

  1. In total, how many wires are coming out of the motor, and what are the colors?
  2. Same question for the resistor: how many total wires are connected to the resistor and what are the colors? Are there two terminals, or three?
  3. is one of the motor wires connected to the resistor (hopefully on the same terminal as the Green/Yellow)?
  4. Does the resistor have continuity?

As long as the motor has only two wires, you should be able to wire it up as David described. If the motor has additional wires, we’ll have to figure it out.

Thanks everyone for your thoughts and comments. Good to know i have an aftermarket motor on it. I won’t have access to the car until the weekend, but I do know that the resistor has 2 terminals on it and there is a green/blue and a green/yellow going to it. I will get some more info this weekend. I’m hoping there is a make and model number on the motor somewhere.

I got the heater motor working! I found a remnant of a connection on the rear side of the resistor and soldered the dangling wire on it and the heater fan spins when I operate the switch in the high speed mode, but not the low… this is a step in the right direction. The switch is brand new…