Tail lights not working

Frobisher

Well-known member
Dec 27, 2012
107
39
Pennsylvania
Ok, so...my tail lights are not working. Fuses are good. Reverse, blinker and brakes all work. What ghost should I chase next?

Dash lights out
I've found that it's usually a bad connection either in the bulb socket, the metal contacts in the light unit itself the socket screws into, or the main harness isn't engaging tightly enough in its plug.
 
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LRDONE

Active member
Dec 3, 2020
32
9
Michigan
When I had tail light trouble it ended up being the bulb socket contacts. If one is crusty, spend the time and clean them all up.
 

wturner

Well-known member
May 21, 2004
1,248
0
Houston
Well…everything was fine until I turned the truck off. The second I turned off the ignition, the fuse blew again.

Any clues?
 

Flyfish

Well-known member
Oct 29, 2004
1,083
91
49
St. Louis
Well…everything was fine until I turned the truck off. The second I turned off the ignition, the fuse blew again.

Any clues?
Which 20A fuse? Side markers, driving lights, horn, hazards Etc?? Which ever it is, I would take a look at the applicable wiring/plugs etc.
 

Frobisher

Well-known member
Dec 27, 2012
107
39
Pennsylvania
Well…everything was fine until I turned the truck off. The second I turned off the ignition, the fuse blew again.

Any clues?
I seem to recall having a short in my bumper marker light. I'd fix the fuse, and it would short out again. It may not be exactly your situation, but it did affect my tail lights as well since they share the same circuit in some weird Lucasian way. At least, that's my memory of it. Maybe check the wiring to your bulb there?
 
Two typical sidelight-position- lights - trouble: 1) tail lights bulb holder: sometimes contact springs touch together with mass peripheral contact
2) standard hidraulic jack sometimes eat light harness insulation. And when damaged line is sidelight, then blows fuse.
You may check these points to discard them.
Ah... i share this search method: instead to replace fuse, you may connect a portable bulb there. Then you can operate everything, touch everywhere in order to get bulb not fully shining. If it is full shining, it is better for searching, because shortcut is present 100% time. This method saves fuses and protects harnesses from burning.
Regards
 
Last edited:

WaltNYC

Well-known member
Mar 3, 2010
585
65
NYC
If you are into tracing wiring diagrams, the entire set of manuals, diagrams, and a whole lot more can be found in the google link in my signature. Help yourself to whatever you need.
 

wturner

Well-known member
May 21, 2004
1,248
0
Houston
Minor update. The fuse blows when I turn the ignition off AND the lights are on. If I turn the lights on and off while the engine is running, no problem. But if I turn the lights on while engine is not running -or- turn the engine off while lights are on, fuse blows. It’s the second fuse from the middle, labeled “Sidelights”.
 

wturner

Well-known member
May 21, 2004
1,248
0
Houston
aftermarket radio?
Yes, I’ve had an aftermarket pioneer for years but the connection behind the detachable face went bad so I replaced it a year or so ago. I don’t think I’ve had it inspected or legally on the road since. So the issue could have gone unnoticed until now….now that I’m trying to get it inspected!!
 

robertf

Well-known member
Jan 22, 2006
4,416
146
-
so I'd unhook it, next suspect would be the ring light around the ignition. then maybe the multifunction unit
 

wturner

Well-known member
May 21, 2004
1,248
0
Houston
so I'd unhook it, next suspect would be the ring light around the ignition. then maybe the multifunction unit
Interesting, I’ve also replaced my ignition switch (the cylinder fell to pieces) since it’s been in the coma (Memorial Day flood in Houston).
 

robertf

Well-known member
Jan 22, 2006
4,416
146
-
does the fuse not blow until the door is opened? if so it maybe the beeping part of the multifunction unit