Author Topic: Change Over in Wiring Harness  (Read 1261 times)

Offline MWM

  • Full Member
  • ***
  • Posts: 197
Change Over in Wiring Harness
« on: June 18, 2012, 12:17:31 AM »
Good Evening,
I have mid march San Jose fastback and I trying to figure out my wiring harness. At what point did thry switch to the resistor on front of the heater box? I have the heater controls, but can't figure where it plugs into the under dash harness. Any photos? I do have a the diagram, but am scratching my head to figure it out.
Thank you!

Offline CharlesTurner

  • Charles Turner
  • Administrator
  • Hero Member
  • *****
  • Posts: 7688
Re: Change Over in Wiring Harness
« Reply #1 on: June 18, 2012, 12:33:46 PM »
Believe the changeover was sometime around March/April of '65.

If you have the original main wiring harness, it will have a black plug for the early style heater switch.  Otherwise, the heater switch has a standalone harness that connects to the resistor.  Heater motor for early setup has 3 wires, later has 2 wires.
Charles Turner - MCA/SAAC Judge
Concours Mustang Forum Admin

Offline MWM

  • Full Member
  • ***
  • Posts: 197
Re: Change Over in Wiring Harness
« Reply #2 on: June 18, 2012, 02:23:08 PM »
Thank you Charles!
I do have a stand alone harness for the heater switch, a resistor on the front of the box and a two wire (brown and yellow) motor. What would be the power source? Is that at the controls or just off the motor?
Thanks!

Offline CharlesTurner

  • Charles Turner
  • Administrator
  • Hero Member
  • *****
  • Posts: 7688
Re: Change Over in Wiring Harness
« Reply #3 on: June 18, 2012, 03:16:13 PM »
Power source is the yellow wire under the dash on the main harness, plugs into the resistor block below the 3-prong connector coming from the fan switch.
Charles Turner - MCA/SAAC Judge
Concours Mustang Forum Admin

Offline MWM

  • Full Member
  • ***
  • Posts: 197
Re: Change Over in Wiring Harness
« Reply #4 on: June 18, 2012, 10:09:14 PM »
Found it! Thank you Charles! I wondered what that yellow wire was for, makes sense now.