• Mustang Forums
  • 2005 - 2014 S-197 Mustang -General/Talk-

Strange Tail Light Problem

  • Thread starter Thread starter Big Studly
  • Start date Start date Mar 9, 2020
B

Big Studly

New Member
Jun 4, 2006
5
0
1
Mar 9, 2020
#1
  • Mar 9, 2020
  • #1
I am going to describe this the best I can, because I find this issue completely strange. This is for a 2008 GT.

Left tail light has sequential tail lights, and work as they should. It appears to have some sort of sequential tail light module installed. The wiring is kind of butchered and the wire colors don't really match the wiring diagram I was able to find online.

The right side tail lamp has an issue with the inside (far left) bulb when the turn signal and hazard lights are on. It doesn't blink. There is no sequential tail light module (car was in a bad accident on this side and apparently wasn't replaced with the replacement tail light), but the bulb does come on when the brakes are pressed. Obviously I am trying to get the bulb to light up when the turn signal/hazard lights are on and deal with the mismatched sequential tail lights after.

So, I tracked down the wiring diagram, and the wiring appears to match, and I have looked at photos online of the stock harness and they appear to be the same as what I am seeing. To this particular bulb there is a dark blue wire with yellow stripe, and two black wires. This is where the strange starts happening. I get out my voltmeter and set it to DCV. I stick the red lead in the connector where the blue pin is, and then ground the other side. The voltage flickers. I am assuming that means I am getting some voltage in that wire. I check both side of the connector, same thing. I also put the red lead inside the bulb housing and touch the metal part, and put the black to ground. Still get a flickering voltage. But...I get no light out of the bulb. I even replaced the bulb from the left side tail lamp to make sure it wasn't the bulb.

SO.....my question is, what should I really be checking here? I think my next step is to really get a good ground and try this again just to make sure I did it correctly, but assuming I did...what could the problem be here? Is this bulb possibly missing a wire and I am reading the wiring diagram incorrectly? Did removing the sequential tail light module screw something up? My first thought is, since I am grounding the signal on an exposed part of the body, I should check the ground of the bulb socket. I tried, but couldn't figure out how to check that specific ground (the common ground for all 3 sockets must be working because the other two bulbs work). Is there a way to get to the wires inside the socket?

Any help is appreciated. Thanks.
 
You must log in or register to reply here.

Similar threads

M
Aftermarket Brake light help needed
  • Mustang Steve
  • Mar 17, 2026
  • 2005 - 2014 S-197 Mustang -General/Talk-
Replies
0
Views
75
2005 - 2014 S-197 Mustang -General/Talk- Mar 17, 2026
Mustang Steve
M
2
Electrical mayhem
  • 2000ElectricGreen
  • Mar 13, 2026
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
2
Views
201
1996 - 2004 SN95 Mustang -General/Talk- Mar 24, 2026
2000ElectricGreen
2
B
Electrical Fuse 8, Light Green / Black Wire
  • bleedinggreen
  • Jun 23, 2025
  • Fox 5.0 Mustang Tech
Replies
7
Views
375
Fox 5.0 Mustang Tech Jun 26, 2025
bleedinggreen
B
Wiring diagram
  • 78 Mach1
  • Sep 24, 2024
  • 1974 - 1978 Mustang II Talk & Tech
Replies
19
Views
1K
1974 - 1978 Mustang II Talk & Tech Jan 24, 2025
welder4956
J
Shift light
  • Jfriedrich
  • Jun 22, 2025
  • SN95 4.6L Mustang Tech
Replies
1
Views
169
SN95 4.6L Mustang Tech Dec 29, 2025
dirk shorter
D
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 2005 - 2014 S-197 Mustang -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?