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Headlights won't work - parking lights do...Any Ideas?

  • Thread starter Thread starter TheUser
  • Start date Start date Sep 26, 2004
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Sep 26, 2004
#1
  • Sep 26, 2004
  • #1
My headlights won't work! The side marker lamps work front and back, but the actual headlights won't work. I checked fuse #4 (headlamp fuse) and it's good. The only thing I've done to the car since the last time they worked was today I added a huge grounding strip from the timing cover where the battery ground wire goes to the sway bar bolt. My O2 ground and chassis-to-motor ground bolts were loose on the back of the heads, so I tightened them up.

So far what i've checked:

Fuse #4
Added MORE ground w/ set of jumper cables
Used jumper cables from my jeep battery for more power
Checked starter relay for the connection there and all of the wires appear to be on there.

It's not a bulb because neither headlight or tailight works.

Any idea's? I'd like to drive it to work tomorrow, but I can't if the lights won't work.

Thanks in advance
 

diablostang

New Member
Sep 21, 2004
425
0
0
Raleigh, NC
Sep 26, 2004
#2
  • Sep 26, 2004
  • #2
I had the same problem, except reversed... I finally removed my headlight switch and here's what I found behind it-

 

87TTopGT

New Member
Dec 21, 2003
173
1
0
Sep 26, 2004
#3
  • Sep 26, 2004
  • #3
If it is the meltdown, do a search- I saw a thread recently about re-wiring with relays to avoid future recurrences...
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Sep 26, 2004
#4
  • Sep 26, 2004
  • #4
Thanks, given your picture and description, I pulled my switch out. I put it back and walla, the headlights and fogs worked, but tails didn't. I moved it around and they wen't off, so it's bad wiring somewhere. I pulled my headlight switch from my LX to make sure and they don't work w/ it either. Now I suppose I'll be checking wires w/ a test light or something. Thanks
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Oct 2, 2004
#5
  • Oct 2, 2004
  • #5
anyone have any ideas what I can do to fix this? I suspect bad wiring, but are they any other possibilites? I see no reason why the extra ground would cause this, but I didn't have this problem before the ground. Probably just coincidence...
 
N

Na5.0HO

New Member
May 29, 2003
342
0
0
Michigan
Oct 2, 2004
#6
  • Oct 2, 2004
  • #6
My headlights just went out as well and after removing my switch I have the same wire "meltdown" as the above picture... if anyone has a link or knows about rewiring... please let us know

Thanx,
Jason
 

silver1983gt5.0

New Member
Sep 7, 2003
116
0
0
sturbridge,massachussets
Oct 2, 2004
#7
  • Oct 2, 2004
  • #7
<< not a mechanic, but i have a chiltons book and it shows all the wiring front to back. dont know if it has the details like you are looking for but i guess its worth a try
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
Oct 2, 2004
#8
  • Oct 2, 2004
  • #8
Na5.0HO said:
My headlights just went out as well and after removing my switch I have the same wire "meltdown" as the above picture... if anyone has a link or knows about rewiring... please let us know

Thanx,
Jason
Click to expand...

search for "GT foglight fix"
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Oct 2, 2004
#9
  • Oct 2, 2004
  • #9
did your marker lights, parking lights, tail lights, etc work when your headlight harness was toasted? The thing is that my side marker lights front and back work and the turn signals, my head lights and tail lights do not, so I don't think the harness is "toast."

Just for kicks, how could I test to see if the harness is toast? I know it's not discolored at all cause my headlight switch has been disconnected all week. Could I supply 12 volts to the wiring at the harness and see if the headlights turn on? Is that possible?

here's the foglight fix diagram:

 

Marks5.0!

Founding Member
Jan 27, 2000
640
2
0
San Antonio, TX
Oct 2, 2004
#10
  • Oct 2, 2004
  • #10
when mine went out my headlight harness was toasted as well as the turn signal/wipers wiring harness
 
B

BlackSunshinelx

New Member
Apr 10, 2003
86
1
0
long island,ny
Oct 2, 2004
#11
  • Oct 2, 2004
  • #11
My headlights dont work, but the high beams and the marker lights do.ITs weird and i do not have the switch meltdown either.
 

RsStanG1987

I shaved all my pubes playing this game.
10 Year Member
Mar 13, 2004
569
9
79
Dupont PA
Oct 2, 2004
#12
  • Oct 2, 2004
  • #12
Maybe your switch is broken. I took my switch out and broke it once and all the lights worked except the head lights. Put a new switch in and bam it worked. The tail light harness runs down the drivers side of the car under the carpet up throught the rear quarter plastics. Check the wiring behind the foglights and make sure that isnt cooked. I would personally do the foglight fix so it doesent mess up your car. Your probabbly gonna have to get a test light and check wires. Make sure you try the easy things first. Bulbs , fuses, switch, and wires from the sitch back.

www.50resto.com sells the little plastic connector to fix this it comes with a thicker guage wire to fix this melt down problem.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 3, 2004
#13
  • Oct 3, 2004
  • #13
TU, im not sure i got all of this, but what i might do:
all you are missing is headlights, right? do brights or flash to pass work?

you could energize the headlight wire at the switch (and confirm that there is continuity in the switch - if you tried another switch, you should be alright). if you energize it, be sure to use a fuse of the same rating as the stock fuse for safety.

dont forget about the Multi function switch. the juice for headlights flows from the headlight switch to the MF switch (so switching from highs to lows can occur). then it goes on. BmorrisJ has a nice pic of his burning up, IIRC.

the red/yellow (not sure that is the color) wire at the MF switch burns or can pop out. then no headlights.

EDIT: in re-reading, you said that just moving the switch made them work (when you popped it in and out)..?? if so, jump all over that switch and the wiring behind it. if a terminal in the connector is loose or the switch is bad, you should find it fast with a DMM.

for ideasof stuff that people do: i have relays on lows, highs and fogs. i like it cuz there is only ~150mA draw on the wiring and switches in the car.

good luck bud.
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
Oct 3, 2004
#14
  • Oct 3, 2004
  • #14
Alright, I went outside to make sure the brights didn't work because I didn't remember checking and now they all work. This is so crazy...It actually makes me mad because I don't want to drive it and then end up w/o lights some night.

I thought the bottom horizontal red section of the tail lights was supposed to light up, but I guess not, so the tails have worked all along. Is that bottom horizontal section supposed to light up or what is it for? It doesn't light up on my LX either.
 
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