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  • 1974 - 1978 Mustang II Talk & Tech

cobra II wiring problems

  • Thread starter Thread starter 69stang351
  • Start date Start date Jun 24, 2004
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69stang351

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Dec 23, 2002
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Spokane, WA
Jun 24, 2004
#1
  • Jun 24, 2004
  • #1
i replaced the backup bulb on the drivers side of my cobra and (dont remember when) it is blown out already it was just replaced on monday. I cant understand it?? maybe the wiring is bad?? i will have to check the driver bulb on the pass. side to see if it still works.
 
L

LedZ 5.0

now you have my pea brain going in circles
Apr 1, 2004
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Jun 24, 2004
#2
  • Jun 24, 2004
  • #2
Check the ground wires along the rear harness and at the bulb sockets. Also check the grounds on the sides of your rad support.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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Jun 24, 2004
#3
  • Jun 24, 2004
  • #3
yup, ground wires and be sure "+" in the socket isn't touching metal anywhere it shouldn't. clean the contacts. was it a brand new bulb or used?
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
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Jun 24, 2004
#4
  • Jun 24, 2004
  • #4
Bad wiring doesn't blow out bulbs, Only thing that blows out a bulb is overvoltage and / or age (besides being shaken)

In my truck I went 3 years without having to replace a brake light bulb. Then I replaced around 6 bulbs in as many months. Now I haven't replaced a bulb in 3 years.

Bad bulbs happen.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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#5
  • Jun 24, 2004
  • #5
Wart said:
Bad wiring doesn't blow out bulbs, Only thing that blows out a bulb is overvoltage and / or age (besides being shaken)

In my truck I went 3 years without having to replace a brake light bulb. Then I replaced around 6 bulbs in as many months. Now I haven't replaced a bulb in 3 years.

Bad bulbs happen.
Click to expand...

if you have wiring that is constantly being shorted...meaning on and off constantly...the bulb isn't going to last for long, especially if its a touchy short where a contact is made immediately after losing the contact for a fraction of a second. in fact, it may not even be noticible to you.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
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Jun 24, 2004
#6
  • Jun 24, 2004
  • #6
1970impala said:
if you have wiring that is constantly being shorted...meaning on and off constantly...the bulb isn't going to last for long, especially if its a touchy short where a contact is made immediately after losing the contact for a fraction of a second. in fact, it may not even be noticible to you.
Click to expand...


Why's that? I could see it in a halogen cycle lamp, not a standard filiment.
 
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dmoody

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Jun 24, 2004
#7
  • Jun 24, 2004
  • #7
Wart is right, overvoltage will kill a bulb but undervoltage (a short) won't.

d
 

69stang351

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Dec 23, 2002
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Jun 24, 2004
#8
  • Jun 24, 2004
  • #8
1970Impala - it was a brand new bulb, I was sure it was working when i left the parts house, but maybe I was wrong, maybe the contacts need cleaned or something, the old bulb could have been fine, who knows?

Anyway, I will check things out today and get back to you all. Thanks for the help!
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jun 25, 2004
#9
  • Jun 25, 2004
  • #9
69stang351 said:
1970Impala - it was a brand new bulb, I was sure it was working when i left the parts house, but maybe I was wrong, maybe the contacts need cleaned or something, the old bulb could have been fine, who knows?

Anyway, I will check things out today and get back to you all. Thanks for the help!
Click to expand...

Good luck and let us know.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Jun 25, 2004
#10
  • Jun 25, 2004
  • #10
69stang351 said:
1970Impala - it was a brand new bulb, I was sure it was working when i left the parts house, but maybe I was wrong, maybe the contacts need cleaned or something, the old bulb could have been fine, who knows?

Anyway, I will check things out today and get back to you all. Thanks for the help!
Click to expand...


Since the newest II is 26 years old it's quite possible there is something wrong with the sockets. And check your grounds, their a known fault in vehicles this old.

I had assumed you checked these things before making your query.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jun 25, 2004
#11
  • Jun 25, 2004
  • #11
Wart said:
Since the newest II is 26 years old it's quite possible there is something wrong with the sockets. And check your grounds, their a known fault in vehicles this old.

I had assumed you checked these things before making your query.
Click to expand...

1970impala said:
yup, ground wires and be sure "+" in the socket isn't touching metal anywhere it shouldn't. clean the contacts. was it a brand new bulb or used?
Click to expand...

Geez, Wart, are you actually agreeing with what I said?
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Jun 25, 2004
#12
  • Jun 25, 2004
  • #12
1970impala said:
Geez, Wart, are you actually agreeing with what I said?
Click to expand...


Don't even try trolling, your no good at it.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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Jun 25, 2004
#13
  • Jun 25, 2004
  • #13
Wart said:
Don't even try trolling, your no good at it.
Click to expand...

what the he** does trolling mean?
 
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77sleeper

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#14
  • Jun 25, 2004
  • #14
think he meant for a compliment
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
Founding Member
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Jun 25, 2004
#15
  • Jun 25, 2004
  • #15
77sleeper said:
think he meant for a compliment
Click to expand...

Oh, in that case. Thanks Wart! (hehe)
 

69stang351

New Member
Dec 23, 2002
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Spokane, WA
Jun 26, 2004
#16
  • Jun 26, 2004
  • #16
hey guys dont hijack my thread!! lol j/k anyway, i havent checked that bulb yet... as i have bigger problems as of recently... yes my wiring harness keeps fusing itself and shorting out... something in my wiring is fishy and i cant tell what yet... checked everything i think... alt., volt. reg., etc. for more info go to this thread... http://forums.stangnet.com/showthread.php?t=476963
 
L

LedZ 5.0

now you have my pea brain going in circles
Apr 1, 2004
204
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0
Jun 26, 2004
#17
  • Jun 26, 2004
  • #17
Replaced the starter relay? Have a good ground connection for the relay on the fender well? Checked the fusible links at the relay and near the harness connecter at the drivers firewall? Check the starter cable for any open area that could be shorting to ground and at the starter connection itself. Check for faulty starter.
 

69stang351

New Member
Dec 23, 2002
191
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Spokane, WA
Jun 26, 2004
#18
  • Jun 26, 2004
  • #18
ok, i do know a lot about cars and the stuff that is under the hood, but starter relay?? where/what is that?? and my solenoid is not bolted tight to my inner fender... could be part of the problem but i know there is something else cuz i directly connected the wiring harness that shorted to the battery to check it for spark and it still did. It could be the starter... that is still hooked up to power... also maybe it could be my ignition switch?? let me know what you think
 
L

LedZ 5.0

now you have my pea brain going in circles
Apr 1, 2004
204
0
0
Jun 26, 2004
#19
  • Jun 26, 2004
  • #19
The starter relay is the solenoid. Tighten it up on the fender well for a good ground.

I can't say for sure if it's your starter but you could disconnect the cable at the solenoid and see if you still have the mean spark problem.
 

69stang351

New Member
Dec 23, 2002
191
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Spokane, WA
Jun 26, 2004
#20
  • Jun 26, 2004
  • #20
Well, I unhooked everything electrical, I mean EVERYTHING, I also unhooked the solenoid and the starter and it still arcs, so it has to be grounded out somewhere, I think it is the little mechanism on my steering column (small mechanical rod) that the ignition switch is connected to that is grounding out a wire, cuz when i connected the wiring harness to the neg. side of the bat. it didnt arc (like when you connect the pos. and neg. terminals)
 
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