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1986 Fog light problem.

  • Thread starter Thread starter irvgotti
  • Start date Start date Feb 3, 2008

irvgotti

New Member
Dec 19, 2005
34
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0
New York city
Feb 3, 2008
#1
  • Feb 3, 2008
  • #1
1986 mustang GT

I installed new fog lights and worked well for months then one shadered with i guess a rock on the road . so im replacing it and when i go to test it to see if it works they dont go on and the light inside the car doesent go on niether indicating my fog lights are on.....so now i think that the fuse is bad but there is no fuse for the fog lamps.. what do i do
 

irvgotti

New Member
Dec 19, 2005
34
0
0
New York city
Feb 7, 2008
#2
  • Feb 7, 2008
  • #2
OK i got some info im looking for the foglight fuse link. by starter relay ???..what the hell is that. and ifanyone knows where is it ??
 
V

v8only

Active Member
Jul 3, 2003
2,378
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49
Feb 7, 2008
#3
  • Feb 7, 2008
  • #3
this is a complicated circuit.

You have to start at the foglights.

probe the foglight connector and make sure you're not getting 12 volts. If you are, you have bad bulbs. if you don't, then next go under the dash.

there is a fog light relay under the dash. This is the thing that goes bad 9out of 10 times. If it goes bad, replace it with a better relay.

the relay is located dr side. it's a small silver box screwed into the dash frame to the left of the steering wheel under the dash.

the way that it works is that it has TWO 12 volt sources coming in, and one 12 volt source going out.

the double green (I believe is the color)...but anyhow the only wires to have two coming out of one slot is where you need to probe for signal going OUT to the fogs. Turn the key on and everything like you would to turn the fogs on.

first probe to see if you have two 12 volt sources coming in. I forget the coloring, but you'll get 12 volts at two different wires going into the relay. If you do, you should then get a single 12 volt signal coming out along those green pair of wire.

if you have both 12 volt signals coming in, but nothing out, your relay is bad.

if one of the two 12 volt signals is bad, then you need to trace those wires back.

let me know if that helps. I have wiring diagrams for all of this....if you're good at tracing those sort of things.
 
V

v8only

Active Member
Jul 3, 2003
2,378
22
49
Feb 7, 2008
#4
  • Feb 7, 2008
  • #4
irvgotti said:
OK i got some info im looking for the foglight fuse link. by starter relay ???..what the hell is that. and ifanyone knows where is it ??
Click to expand...

there are a couple of fuseable links like you said. If those break, then your fogs won't work. This is what happened to my bro.

those fuseable links are the blue ones located DIRECTLY on that fat harness coming out of the firewall on the pass side. they stick outside of the main harness.

I just grabbed a couple of junkyard fuseable links, and saudered them in
 
S

Slo86GT

New Member
Feb 7, 2008
2
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0
Southaven, MS
Feb 7, 2008
#5
  • Feb 7, 2008
  • #5
I know this is a lame request, but also make sure that the key is in the ON position, or the fog lights will not turn on.

I did this one when I replaced my first bulb. /bonkhead
 
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