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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Electrical 89 LX 5.0 Dash light issues

  • Thread starter Thread starter Fast89GWILL
  • Start date Start date Mar 25, 2019

Fast89GWILL

New Member
Mar 25, 2019
13
1
3
Charlotte
Mar 25, 2019
#1
  • Mar 25, 2019
  • #1
Hi,

Fist post here so thanks for welcoming!

Have an 89 mustang and headlights work, turn signals,interior lights, etc...

Issue is when I turn on the headlight switch my dash lights don't turn on. The dimmer switch also doesn't do a thing.

Am going to check the fuse tonight first but what are your experiences with the headlight switch vs dimmer?

I've read a handful of posts here so have some direction, but still a bit grey.

Thanks.
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Mar 25, 2019
#2
  • Mar 25, 2019
  • #2
GT or LX?
 

Fast89GWILL

New Member
Mar 25, 2019
13
1
3
Charlotte
Mar 25, 2019
#3
  • Mar 25, 2019
  • #3
LX 5.0
 

Fast89GWILL

New Member
Mar 25, 2019
13
1
3
Charlotte
Mar 25, 2019
#4
  • Mar 25, 2019
  • #4
Quick update.

With the car on I tested the head light switch on and off. . When off the blue/red has no current. When on it does.

When on I traced that to the dimmer switch which also has power on the blue red. Traced that blue/red to the instrument panel and it has power to the back of the dash.

Starting to think its the cluster.

Anyone have experience with this?
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Mar 29, 2019
#5
  • Mar 29, 2019
  • #5
The cluster is not part of the circuit.
You need to consult the EVTM.

View: https://drive.google.com/open?id=1on5czXKmpETzxUggWTGtoUuVkJT2UUxN
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Mar 29, 2019
#6
  • Mar 29, 2019
  • #6
The cluster is not part of the circuit.
You need to consult the EVTM.

View: https://drive.google.com/open?id=1on5czXKmpETzxUggWTGtoUuVkJT2UUxN
 

Fast89GWILL

New Member
Mar 25, 2019
13
1
3
Charlotte
Mar 29, 2019
#6
  • Mar 29, 2019
  • #6
Thanks a gazillion for sharing that! Will print this off.
 

Fast89GWILL

New Member
Mar 25, 2019
13
1
3
Charlotte
Apr 8, 2019
#7
  • Apr 8, 2019
  • #7
Thanks for everyone's insight on this. Traced everything over some spare time and it was the ground wire. The one right behind the batter a ways. Re-grounded and then decided to redo all the grounds where I could. Amazing how much brighter and consistent some of the electrical got. Thanks again!
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Apr 9, 2019
#8
  • Apr 9, 2019
  • #8
Did you notice that all the grounds have green tinted metric screws?
 
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