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'66 Mustang backup light wiring, under dash

  • Thread starter Thread starter Cobra281s
  • Start date Start date Jun 23, 2019

Cobra281s

New Member
Jun 23, 2019
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Iowa
Jun 23, 2019
#1
  • Jun 23, 2019
  • #1
I'm struggling with the wiring under the dash for the backup lights for my '66 Mustang. The lights didn't work when I bought the car. The switch in the transmission was crap. I replaced it with wiring to the inside of the car. I see where the 2 wires are that come from the switch, from under the carpet, by the hump to use the dash. The male is connected to a black/red that I bugged out and is connected to 12v accessories. The female...no clue where it goes. I see no male wire even close. I ran an external wire from that female, directly to the connection in the trunk, everything works. So my question is, where....under the dash, is the wire connection from the black/red from the trunk backup light? I know it must come in from the driver side by the fuse box, but where is the male connection that hooks up to the switch by the hump under the dash?

Thank you SO much in advance!
 

dennis112

15 Year Member
May 15, 2005
1,561
36
79
Amish Wonderland of Central PA.
Jun 24, 2019
#2
  • Jun 24, 2019
  • #2
Cobra281s said:
I'm struggling with the wiring under the dash for the backup lights for my '66 Mustang. The lights didn't work when I bought the car. The switch in the transmission was crap. I replaced it with wiring to the inside of the car. I see where the 2 wires are that come from the switch, from under the carpet, by the hump to use the dash. The male is connected to a black/red that I bugged out and is connected to 12v accessories. The female...no clue where it goes. I see no male wire even close. I ran an external wire from that female, directly to the connection in the trunk, everything works. So my question is, where....under the dash, is the wire connection from the black/red from the trunk backup light? I know it must come in from the driver side by the fuse box, but where is the male connection that hooks up to the switch by the hump under the dash?

Thank you SO much in advance!
Click to expand...

Have you looked for connections on the engine side of the fire wall right behind the motor? Seems to be that might be where they are.
 

Cobra281s

New Member
Jun 23, 2019
3
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1
Iowa
Jun 24, 2019
#3
  • Jun 24, 2019
  • #3
dennis112 said:
Have you looked for connections on the engine side of the fire wall right behind the motor? Seems to be that might be where they are.
Click to expand...

I looked on the engine side, nothing there.
 

tos

Founding Member
Apr 27, 2001
896
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Cincinnati Ohio
Jun 27, 2019
#4
  • Jun 27, 2019
  • #4
Where did the old switch plug into? You should have a connector right behind the engine above the bell housing
 

Cobra281s

New Member
Jun 23, 2019
3
0
1
Iowa
Jun 29, 2019
#5
  • Jun 29, 2019
  • #5
tos said:
Where did the old switch plug into? You should have a connector right behind the engine above the bell housing
Click to expand...
I bought the car a couple of years ago, the backup lights never worked. When I looked at the switch on the actual transmission, I saw a wire was broke off. I installed a new switch and it had a new wire with a grommet that I pulled up through the hole in the transmission hump by the shifter. Once inside, that wire runs under the carpet, by the heater distribution box up under the center of the dash. 1 the male connector was plugged in but the female was not hooked up. When I bugged out the male, it was hooked up to 12V accessory. So that's my power and I assumed the female goes to the backup lights. If I run a wire from that directly to the trunk and lights, all is good. So I just need to find where the factory wire from the trunk to under the dash is. I was hoping someone knew where to look for that wire under the dash. I have even taken the dash out and can't find the open connection.
 
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