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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Completely new wiring and headlight problem

  • Thread starter Thread starter ChewiesDad
  • Start date Start date Jul 22, 2009
C

ChewiesDad

New Member
Feb 5, 2004
30
0
0
Palm Beach Gardens, Florida
Jul 22, 2009
#1
  • Jul 22, 2009
  • #1
Hi all. I just rewired my 87 from bumper to bumper using an aftermarket kit. Everything is wired correctly and was working fine including flashers, turn signals, low and high beams, and indicator lights (completely aftermarket gauge cluster, no factory stuff).

After working fine, the headlights stopped working. The flash to pass works fine.

Now, those of you familiar with the wiring know this:
Power comes into the switch from two sources, the tan/white and the heavier black/brown (if I recall correctly). There is obviously power to the switch.

The red/yellow wire exits the headlight switch and enters the multi-function switch where it supplies power to the outputs for the low and high beams (and indicators).

The problem is when the switch is in the "on" position, there is no power to the red/yellow wire. Using a small jumper wire between either power source and the red/yellow turns the lights on instantly.

I replaced the headlight switch with another one but the same problem exists. Note: I bought another USED switch, so maybe that's the issue?
 

TechSteele

New Member
Mar 8, 2009
60
1
0
North Coast
Jul 22, 2009
#2
  • Jul 22, 2009
  • #2
Dosent sound like the switch, sounds like a bad wire, or connection.
Check the power on the contacts in side the plug, and then check for continuity for the switch, hitting the contacts with a multimeter when switched into the on position. It will show a circuit if it works, nothing if bad.
That would say for sure if the switch works, or bad wire/connection.

Edit* unplug the pigtail from the switch and test seperate. (Incase i didnt make that part clear)
 
C

ChewiesDad

New Member
Feb 5, 2004
30
0
0
Palm Beach Gardens, Florida
Jul 22, 2009
#3
  • Jul 22, 2009
  • #3
Thanks.

I went ahead and checked the plug. Using a jumper wire, the headlights power right up.

I put 12v to the "I" terminal in the switch. Turning the switch on should allow power to flow to the "H" terminal. It doesn't. It does, however, jump from "B2" to "R" like it is designed to do.

I'm thinking I got two bad switches....ugh.
 

TechSteele

New Member
Mar 8, 2009
60
1
0
North Coast
Jul 22, 2009
#4
  • Jul 22, 2009
  • #4
Two bad switches would be even bad luck for me, and if it wasnt for bad luck i would have no luck at all, hehe
Try sqirting it with some contact cleaner before trying to buy a 3rd.

Its just odd that 2 would go, or be bad. (unless something is being melted inside maybe?)
I dont have much in the way of ideas for this one, but sounds like you are doing everything possible.
 

Saleen0679

10 Year Member
Apr 14, 2005
876
24
49
Yakima, WA
Jul 23, 2009
#5
  • Jul 23, 2009
  • #5
ChewiesDad said:
I put 12v to the "I" terminal in the switch. Turning the switch on should allow power to flow to the "H" terminal. It doesn't. It does, however, jump from "B2" to "R" like it is designed to do.
Click to expand...

Applying power to the 'I' terminal will not send power to the 'H' terminal. The 'I' terminal is for the switch illumination circuit and only lights up the headlight symbol on the switch. The 'B1' terminal is the input for the switched circuit out to the 'H' terminal. If you need a diagram for the switch see post #17 at Headlights not working - Mustang Forums at StangNet.
 
C

ChewiesDad

New Member
Feb 5, 2004
30
0
0
Palm Beach Gardens, Florida
Jul 23, 2009
#6
  • Jul 23, 2009
  • #6
Saleen0679 said:
Applying power to the 'I' terminal will not send power to the 'H' terminal. The 'I' terminal is for the switch illumination circuit and only lights up the headlight symbol on the switch. The 'B1' terminal is the input for the switched circuit out to the 'H' terminal. If you need a diagram for the switch see post #17 at Headlights not working - Mustang Forums at StangNet.
Click to expand...

Thatis it! Bro, I can't thank you enough. This is the second time you bailed me out.

What happened is I removed the light blue/red and grounds as I don't need the switch illumination. Now that I had two empty pin locations, I put the red/yellow back on the wrong one. Not realizing this, I found I had no lights and assumed that I had the wire locations correct and that the switch went bad.

Just had the red/yellow on the opposite side of the switch...

THANK YOU ALL VERY MUCH!
 
C

ChewiesDad

New Member
Feb 5, 2004
30
0
0
Palm Beach Gardens, Florida
Jul 23, 2009
#7
  • Jul 23, 2009
  • #7
Tech Steele, didn't mean to exclude you. Thank you for your help and input as well!
 
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