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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Headlight Problem

  • Thread starter Thread starter MikeStang00GT
  • Start date Start date Mar 14, 2004

MikeStang00GT

Street Master
Founding Member
Jun 17, 1999
1,193
0
0
New York City
Mar 14, 2004
#1
  • Mar 14, 2004
  • #1
Hey guys, I have been having a weird headlight problem. I melted my headlight sockets a while back due to the Xenon bulbs so I bought some new heavy duty ones capable of 120w. I hooked them up and ever since my fogs wont go on with my headlights. Also the high beam indicator is on in the dash but not full on. I can still switch between low and high beams and then the indicator is reallly bright. I tried different combos on the two wires and it doesn't change anything. The only thing I did notice is that when my car is off I can have the headlights and fogs on but when I crank it the fogs won't stay on with the headlights. The fogs will stay on with the parking lights on but not with the headlights on. What could it be? The alternator or could the heavy duty headlight sockets be causing this. Oh by the way I tried hooking up the stock bulbs and I still have the same problem so I don't think its the Xenon bulbs. Thanks for any advice.
 
2

2002BLGT

Well-Known Member
Dec 18, 2003
2,945
4
59
Bedford VA
Mar 14, 2004
#2
  • Mar 14, 2004
  • #2
sounds to me like it might have shorted something in the dimmer switch , but really not sure about that one , I would maybe try to replace your dimmer switch next unless anybody else has a better idea ??
 

MikeStang00GT

Street Master
Founding Member
Jun 17, 1999
1,193
0
0
New York City
Mar 14, 2004
#3
  • Mar 14, 2004
  • #3
Thanks. I'll look into it. Anyone else care to chime in?
 
R

Ron Jeremy

New Member
Nov 13, 2003
747
1
0
Hollywood, California...I live next door to Jenna
Mar 15, 2004
#4
  • Mar 15, 2004
  • #4
Could be that a little mouse might have chewed up some of your wires causing a short. I know that mice can get into the engine bay or even inside the car and cause electrical problems by chewing up wires.
 
N

n0v8or

10 Year Member
Aug 23, 2003
604
8
39
Rhode Island
Mar 15, 2004
#5
  • Mar 15, 2004
  • #5
When you wired the new sockets, the ground connection was omitted, or the wires connected to the wrong terminals. The low beam and high beam filaments are now operating in series, each with half the voltage (they should look dim). With about 6V across the high beams and high beam indicator, it is on but dim whenever the low beams are on.
With the car off, system voltage is about 12.6V, and 6.3V (half of 12.6) is not enough to pull in the fog light inhibit relay, so the fog lights function. When you run the alternator, system voltage increases to 14V-16V, and the 7V-8V across the inhibit relay is enough to trip it . . . . so fog lights turn off. The purpose of the inhibit relay is to turn off the fog lights whenever high beams are on. This is a requirement in some countries.
 
N

n0v8or

10 Year Member
Aug 23, 2003
604
8
39
Rhode Island
Mar 15, 2004
#6
  • Mar 15, 2004
  • #6
A high resistance ground connection will produce the same symptoms, and is even more likely.
 

MikeStang00GT

Street Master
Founding Member
Jun 17, 1999
1,193
0
0
New York City
Mar 16, 2004
#7
  • Mar 16, 2004
  • #7
Sounds good I'll check it out. Thanks for the help.
 

red98_gt

New Member
Mar 15, 2004
69
0
0
Mar 16, 2004
#8
  • Mar 16, 2004
  • #8
My advice to you would be too take it to your local ford garage and let them deal with it...I have had bad experiences with Ford headlights! They will fix em and gaurente em! Sorry, I dont have a solution better than that...but thats what I inevetiably did after great annoyance.
 
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