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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Electrical Nightmares...

  • Thread starter Thread starter Dugan
  • Start date Start date Mar 19, 2009

Dugan

New Member
Mar 21, 2007
47
0
0
Portage Mi
Mar 19, 2009
#1
  • Mar 19, 2009
  • #1
Well, lets see, my brake lights stay on..always. As do my instrument cluster lights, and dome light. And now to make things worse it will not shut off...at all. Starts fine, turn the key off and it stays running. This isn't it dieseling as there is NO change in anything when I take the key out.

Are these three different problems, or do you think they are all related? What do you think is causing it?

I'm wondering if it isn't just time to re-do all the wiring, I hope not though, not looking forward to that.

It has an HEI distributor in it, and the engine is a 68 302.
Resistor wire that used to run from the original coil to the ignition switch has been replaced with a wire that delivers 12v instead of the 8 or whatever.

The brake lights have been giving me this problem for about 1 year. The dome light/instrument cluster lights only started last fall when I parked it for the winter.
It staying running has only been like this for 3 days now.
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Mar 19, 2009
#2
  • Mar 19, 2009
  • #2
So, Let me get it straight:
The brake lights, instrument lights, and dome light stay on all the time whether or not the car is turned on or not?
It might be time to redo the wiring if it's original wiring.
But do you know if the light switch works or not. The instrument gauge, and brake lights get their power from the light switch.
 

Dugan

New Member
Mar 21, 2007
47
0
0
Portage Mi
Mar 19, 2009
#3
  • Mar 19, 2009
  • #3
suki243 said:
So, Let me get it straight:
The brake lights, instrument lights, and dome light stay on all the time whether or not the car is turned on or not?
It might be time to redo the wiring if it's original wiring.
But do you know if the light switch works or not. The instrument gauge, and brake lights get their power from the light switch.
Click to expand...

I was thinking the same thing. Though it is not what I want to hear..I hate electrical work.

Yes as long as the battery is hooked up the Brake lights, Instrument cluster lights, and dome light stay on.

I thought it might be the light switch, but someone told me that it would only be the case if it were the tail lights, and not the brake lights.
 

Mil1ion

New Member
Feb 26, 2009
48
0
0
Mar 19, 2009
#4
  • Mar 19, 2009
  • #4
Well, here are some things to ponder.

Everything to do with T/S's, park and brake lights runs through the Turn signal switch.

Instrument cluster lights run with a power feed from the headlight switch to the cluster via a BLUE/Red Stripe wire.

1) Having a WRONG Brake light switch that is mounted on the nub of a brake pedal can actuate and turn the brake lights on all the time.

Have you tried disconnecting the steering column connector and seeing what happens?
Have you inspected the wiring under the dash ?

Perhaps it is time to disconnect the Ground cable from the battery ,remove the cluster and look around at the wiring behind the cluster ?
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
Mar 19, 2009
#5
  • Mar 19, 2009
  • #5
Ignition switch or module? Ive had a few issues with the electrical switch on the column on older fords. This could keep the car running when you turn it off.
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Mar 19, 2009
#6
  • Mar 19, 2009
  • #6
The brake lights still go through the light switch

Here are a few wiring diagrams, i'm not sure which year car you have
Vintage Mustang Wiring Diagrams

Wiring looks like it'll be a mess and looks hard initially but once you dive in, with a multimeter, you'll get through it. Its not that bad in the end. The forum has loads of great advice too Tim is really experienced and knowledgeable.
 
T

terrylewisii

New Member
Oct 25, 2009
2
0
0
Oct 25, 2009
#7
  • Oct 25, 2009
  • #7
wiring nightmare!! Blinker and gas light

i have a 87 mustang 5.0... for some reason my blinker dont wanna work.. its not the fuse cuz i changed that.. i think its something going on with the wiring but the thing is i dont know what wires are for the blinkes so i can trace them. And my gas meter isnt reading and the gas light stays on...Any one know what this can be????
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Oct 25, 2009
#8
  • Oct 25, 2009
  • #8
Brake lights and turn signals do not get power from the light switch, at least on a 68 or earlier Mustang. Parking/tail lights do not go through the turn signal switch. They are completely different circuits. The brake lights, even though they are powered separately form the turn signals, do go through the turn signal switch. The ignition switch is not on the steering column.
Gene
 

Edster

Founding Member
Aug 13, 2000
500
1
19
League City, Texas
Oct 25, 2009
#9
  • Oct 25, 2009
  • #9
Check the fuse box to see if a previous owner had tried to rig something up. I had a '64 Falcon that had strange issues with parking lights and turn signals. The previous owner tried to "give" the car emergency flashers (which are not a requirement if the car did not have them). Also there may be something wrong w/ the ignition switch or some wires are crossed.
 

Dark Knight

Founding Member
Feb 1, 2000
2,578
0
0
Chandler, Az.
Oct 25, 2009
#10
  • Oct 25, 2009
  • #10
terrylewisii said:
i have a 87 mustang 5.0... for some reason my blinker dont wanna work.. its not the fuse cuz i changed that.. i think its something going on with the wiring but the thing is i dont know what wires are for the blinkes so i can trace them. And my gas meter isnt reading and the gas light stays on...Any one know what this can be????
Click to expand...

Wrong forum And did you replace the flasher?
 
T

terrylewisii

New Member
Oct 25, 2009
2
0
0
Oct 27, 2009
#11
  • Oct 27, 2009
  • #11
Dark Knight said:
Wrong forum And did you replace the flasher?
Click to expand...

im sorry im new to this, but i replaced the flasher.. in fact the old one was still good. cuz my hazards work..
 
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