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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Flashing Fog Lights

  • Thread starter Thread starter wakeboardan
  • Start date Start date Mar 22, 2009
W

wakeboardan

Founding Member
Mar 6, 2002
611
0
0
San Diego
Mar 22, 2009
#1
  • Mar 22, 2009
  • #1
The other night I heard a faint click, and saw my fog lights ficker off for about 5 seconds, then the same faint click occured, and the lights were back on. Tonight, about 10 minutes into my drive, the same thing happened. Could this be a faulty fog light switch?
 

Tim65GT

Active Member
Feb 24, 2004
1,149
2
39
West Texas
Mar 22, 2009
#2
  • Mar 22, 2009
  • #2
Did you have your headlights on too? If so, they would have flickered too. The light switch has a built-in self re-setting circuit breaker and will open when too much current goes through it. Shortly afterward (sometimes less than a second) it cools and closes again giving the flicker effect.

The tail/brake lamps and Fog Lamps pick up their power from the Light Switch. As our cars get old the resistance in the wiring and connnectors increase and cause the CB to trip. A new light switch will help, but will eventually do the same thing. A new harness is an expensive fix, but relays are a popular alternative fix.

here is a recent thread on headlight relays
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Mar 22, 2009
#3
  • Mar 22, 2009
  • #3
wakeboardan said:
The other night I heard a faint click, and saw my fog lights ficker off for about 5 seconds, then the same faint click occured, and the lights were back on. Tonight, about 10 minutes into my drive, the same thing happened. Could this be a faulty fog light switch?
Click to expand...

Could be a bomb in there..............................Better give the car to someone else before it blows.
 
W

wakeboardan

Founding Member
Mar 6, 2002
611
0
0
San Diego
Mar 24, 2009
#4
  • Mar 24, 2009
  • #4
The headlights remained on while the fogs flashed. I took a look at the headlight rewire guide, which i'm gonna definitely do this weekend regardless. It seems that I need to do a similar rewire to the fog lights as the headlights (taking battery power directly). Would that be too much-- overkill??? The factory wiring/terminals looks good, both fog and headlight switches are clean.
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Mar 26, 2009
#5
  • Mar 26, 2009
  • #5
The fog lights should have their own circuit breaker as well. That is probably the problem. If you look in just about any of the Mustang parts places catalogs you will see what it looks like. I think if they are original fog lights the it might be mounted on or near the windshield wiper motor. If the fog lights were added later, it could be anywhere under the dash. Its a small box with 2 terminals on it.

If you want to upgrade your headlght wiring then get a relay kit like this one. Painless makes the same thing, but its twice as much. I have this kit on my '65. Also, get a good pair of halogen sealed beams like GE Nighthawk (not sport) or Sylvania Xtravision bulbs. Don't get any of the ones that say whiter etc. They have a coating on the halogen capsule and actually reduce the amount of light comming out.

RJM Injection Tech Headlight Harness
 
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