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Blinkers and running lights not working

  • Thread starter Thread starter Blueinfan
  • Start date Start date Mar 28, 2022
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Blueinfan

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Mar 18, 2021
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Mar 28, 2022
#1
  • Mar 28, 2022
  • #1
Car: 1991 Ford Mustang LX Convertible - 89,000 miles

Hi All,

I have an issue were the left and right turn signals and running lights do not work in the front. No blinkers in the rear work. Running lights do work.

The hazards do work. In pic1 I have replaced the items that have a red X

The fuse with the light has also been replaced.

All new bulbs have been installed with new headlight hardness purchased from LMR.
 

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bird_dog0347

still married haven't seen testicles in years
15 Year Member
Jun 7, 2012
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Little Elm, TX
Mar 28, 2022
#2
  • Mar 28, 2022
  • #2
I had a similiar issue a few years ago, there was a wire that was loose behind the hazard switch, I think it was orange... check there first.
 
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Blueinfan

Active Member
Mar 18, 2021
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Mar 28, 2022
#3
  • Mar 28, 2022
  • #3
bird_dog0347 said:
I had a similiar issue a few years ago, there was a wire that was loose behind the hazard switch, I think it was orange... check there first.
Click to expand...
ok, I will have to check. What was that wire for? Any idea?

thanks,
 
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Blueinfan

Active Member
Mar 18, 2021
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Mar 28, 2022
#4
  • Mar 28, 2022
  • #4
bird_dog0347 said:
I had a similiar issue a few years ago, there was a wire that was loose behind the hazard switch, I think it was orange... check there first.
Click to expand...
Should I be able to see that wire if I remove the hazard's switch?
 

bird_dog0347

still married haven't seen testicles in years
15 Year Member
Jun 7, 2012
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Little Elm, TX
Mar 28, 2022
#5
  • Mar 28, 2022
  • #5
Blueinfan said:
Should I be able to see that wire if I remove the hazard's switch?
Click to expand...
Yes, it plugs into the back of the switch, I don't recall what it's for and don't have my car here with me to go look.
 
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Blueinfan

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Mar 28, 2022
#6
  • Mar 28, 2022
  • #6
bird_dog0347 said:
Yes, it plugs into the back of the switch, I don't recall what it's for and don't have my car here with me to go look.
Click to expand...
sure enough that Orange wire was out!!!

Thank you

However, running lights in the front are not working. The headlight harness is new.

Hazards, turn signals in the front and rear are working, rear running lights are working.
 
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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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Mar 28, 2022
#7
  • Mar 28, 2022
  • #7
Have you checked the multi function switch for burn connector/wires?
 
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Blueinfan

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#8
  • Mar 29, 2022
  • #8
bird_dog0347 said:
Yes, it plugs into the back of the switch, I don't recall what it's for and don't have my car here with me to go look.
Click to expand...
fixed
General karthief said:
Have you checked the multi function switch for burn connector/wires?
Click to expand...
Yes, I have checked and tripled checked and nothing.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,901
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polk county florida
Mar 29, 2022
#9
  • Mar 29, 2022
  • #9
Headlights work right?
 

manicmechanic007

5 Year Member
Sep 26, 2017
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Mar 29, 2022
#10
  • Mar 29, 2022
  • #10
Damn straight a factory man is going to plug a known good switch into your harness straight away
And if the wires have issues you will find that straight away as well
Pull out or melt is what those wires do best
After they get loose they start to melt (high resistance makes big heat)
I told you the story where the engineers were bragging about having 6 miles of wire in the new then new Fords? (mid 90's)
We told them "well you need eight" We cant even get the headlight switch out"
And of course the TS switch wires are not long enough to use the tilt without them pulling themselves out of the harness
Ford is not alone on this problem
K car Chryslers were actually worse and would shut off driving down the road if you used the tilt
 
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Blueinfan

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#11
  • Mar 29, 2022
  • #11
General karthief said:
Headlights work right?
Click to expand...
Yes, headlights do work
front and rear Hazards work when activated, I could hear the clicking going on the flasher on the fuse box
front and rear turn signals work when activated, I could hear the clicking going on the flasher under the radio
license plate lights work

I have replaced:
1. #14 w/ 20A Circuit break
2. Flasher on the fuse board/box
3. Flasher behind the radio
4. All new front and rear light bulbs
5. New headlight harness
6. Hazard/ convertible top switch
7. Headlight switch
8. Lic plate LEDs



No running lights at all.
 

manicmechanic007

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Mar 29, 2022
#12
  • Mar 29, 2022
  • #12
Start tracing wires
You got something unplugged?
Or you have a broken wire somewhere behind the dash maybe
 
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Blueinfan

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Mar 29, 2022
#13
  • Mar 29, 2022
  • #13
Blueinfan said:
Yes, headlights do work
front and rear Hazards work when activated, I could hear the clicking going on the flasher on the fuse box
front and rear turn signals work when activated, I could hear the clicking going on the flasher under the radio
license plate lights work

I have replaced:
1. #14 w/ 20A Circuit break
2. Flasher on the fuse board/box
3. Flasher behind the radio
4. All new front and rear light bulbs
5. New headlight harness
6. Hazard/ convertible top switch
7. Headlight switch
8. Lic plate LEDs



No running lights at all.
Click to expand...
 

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Blueinfan

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#14
  • Mar 29, 2022
  • #14
Added pictures of what the fuse box looks like, n two other pictures with two other wires with no connection n looks like a ground wire missing
 

manicmechanic007

5 Year Member
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Mar 29, 2022
#15
  • Mar 29, 2022
  • #15
Your car may not use all those connectors depending on options like cruise and clutch.
The big white one might be the key in ignition buzzer
I would have you check power to each socket and out of the headlamp switch for the no park lamps issue
The wrong bulbs a possibility?
Socket failure a possibility
 
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manicmechanic007

5 Year Member
Sep 26, 2017
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Mar 29, 2022
#16
  • Mar 29, 2022
  • #16
You should have a black with orange power wire into the switch
Then the brown is the exterior lamp feed that goes to each park lamp
 
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Blueinfan

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Mar 18, 2021
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Mar 30, 2022
#17
  • Mar 30, 2022
  • #17
ok, so did some further testing.

As I mentioned the headlight harness is brand new from LMR.

1. With hazards on, the low coolant level indicator flashes just like the hazards
2. Driverside headlight flashes off/on like the hazards
3. if I turn off the hazards, and turn on the headlight the parking light is very dim
4. Checked the driver side marker light with a voltmeter and got 3.5 - 7.41 volts and nothing over while the car was on.
5. Replaced and test the new bulbs and replaced all the fuses.

Nothing was modified in the car. Just took out the old headlight harness and placed a new one.



BUT - Did upgrade to a new 1986-93 MUSTANG SVE 130 AMP ALTERNATOR FULL UPGRADE KIT - BLACK

https://lmr.com/item/SVE-17046K2-B/mustang-130-amp-alternator-upgrade-sve-86-93-black
 

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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,901
10,555
203
polk county florida
Mar 30, 2022
#18
  • Mar 30, 2022
  • #18
You likely have a ground wrong. Do you have all the grounds in one place?
 
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manicmechanic007

5 Year Member
Sep 26, 2017
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Mar 30, 2022
#19
  • Mar 30, 2022
  • #19
It's time for another what correct? harness
 
Reactions: Blueinfan

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,901
10,555
203
polk county florida
Mar 30, 2022
#20
  • Mar 30, 2022
  • #20
No, he just has a wire crossed, grounded or two wires touching.
 
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