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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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No Headlights - can flick on bright lights

  • Thread starter Thread starter ChevelleStang
  • Start date Start date Apr 22, 2011

ChevelleStang

Member
Apr 22, 2011
7
1
13
Apr 22, 2011
#1
  • Apr 22, 2011
  • #1
I have a 1990 GT Conv. - im having headlight problems. When I turn on the parking lights and then the headlights, I have the parking lights on but i get no headlights. I thought it was the duel filament bulb. So i bought new headlight bullbs, NOT THE PROBLEM. So i bought a new Headlight/Fog Light switch for the dash, NOT THE PROBLEM. Im not sure where to look now. I am going to pull the switch out and check to see if any of the adaptors for the switch have been burned? Guys, i need some help. Anybody have anything else I can check?
 

LarsD

Founding Member
Jul 2, 2002
2,680
119
123
Texas
Apr 22, 2011
#2
  • Apr 22, 2011
  • #2
Perhaps it is the headlight relay? I'm not super familiar with the headlight wiring on Foxes, but I assume it has to have one.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Apr 22, 2011
#3
  • Apr 22, 2011
  • #3
No headlight relay.

What do you mean about being able to flick on the bright lights?

If flash-to-pass illuminates both lows and highs, look at the red/yellow feed from the hdlt switch where it enters the MF switch. The wire can back out and/or burn.
 

ChevelleStang

Member
Apr 22, 2011
7
1
13
Apr 22, 2011
#4
  • Apr 22, 2011
  • #4
When I push in the button on MF switch. The parking lights come on but low lights don't. But the MF switch for turn signals, I can push forward to put the brights on doesn't work, but I can pull that lever to me to flash the brights and they will come on. As long as I have that lever held toward myself the bright lights stay on. Do you think a wire is burned from the adaptor to the mf switch for the head/fog lights?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Apr 22, 2011
#5
  • Apr 22, 2011
  • #5
When you use FTP, do both lows and highs come on or just one of the other?
 

ChevelleStang

Member
Apr 22, 2011
7
1
13
Apr 24, 2011
#6
  • Apr 24, 2011
  • #6
Both the highs and lows come on when I use FTP.
 

LarsD

Founding Member
Jul 2, 2002
2,680
119
123
Texas
Apr 24, 2011
#7
  • Apr 24, 2011
  • #7
HISSIN50 said:
No headlight relay.
Click to expand...

No wonder these cars burn up the headlight switch so easily.

ChevelleStang said:
Both the highs and lows come on when I use FTP.
Click to expand...

Sounds like the MF switch might be your problem. Are you handy with a DMM? Might want to pull it out and test it.
 

ChevelleStang

Member
Apr 22, 2011
7
1
13
Apr 24, 2011
#8
  • Apr 24, 2011
  • #8
Its not the MF switch. I just put a brand new one in. Iam going to order the adaptors for the headlight and fog lights that connect from the harness to the switch. I'm hoping maybe a wire is burned on the adaptor.
 

MarcMonteverde

New Member
Sep 4, 2006
66
0
0
S@c-ToWn
Apr 24, 2011
#9
  • Apr 24, 2011
  • #9
check your head light ground wire, had a similar problem was really lose so i cleaned the paint where the ground goes and tighten it and it was good, happned outta no where too
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Apr 24, 2011
#10
  • Apr 24, 2011
  • #10
ChevelleStang said:
Both the highs and lows come on when I use FTP.
Click to expand...

HISSIN50 said:
If flash-to-pass illuminates both lows and highs, look at the red/yellow feed from the hdlt switch where it enters the MF switch. The wire can back out and/or burn.
Click to expand...

How did that wire look and did it have continuity?

Since low and high function in FTP, the wiring from the MF switch to the lights should be fine. It's an issue between the hdlt switch and the MF switch.
 

ChevelleStang

Member
Apr 22, 2011
7
1
13
Apr 27, 2011
#11
  • Apr 27, 2011
  • #11
I have been really busy this week and have not had a free minute to get out and check the wires behind the MF switch and the ground wire. Please keep a look out on this thread for me. i am going to try and look at all of that one day this week and for sure over the weekend. i will respond as soon as i get a chance to look at it. Thanks for the help!
 

Mitzoplix

New Member
May 1, 2011
9
0
1
Henderson,Texas
Aug 24, 2011
#12
  • Aug 24, 2011
  • #12
im having the same problem but i have a 1985 mustang 5.0 carb
 
E

elipat

New Member
Oct 7, 2011
2
1
0
Nov 12, 2011
#13
  • Nov 12, 2011
  • #13
im having the exact problem with lights. working on it now!!!! i have pwer inside but not getting outside
 
E

elipat

New Member
Oct 7, 2011
2
1
0
Nov 12, 2011
#14
  • Nov 12, 2011
  • #14
I figured it out...it's the MFS!!! See the red w/yellow tracer wire in ur light switch? It goes to the MFS....that's the signal wire to the MFS.....if you turn ur lights on ..... the red w/black tracer should have power....if it does not it's ur MFS.
 
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