86 tail lights dead short
Thread Starter
Burning Brakes
Joined: Nov 2014
Posts: 936
Likes: 51
From: Post Falls ID
86 tail lights dead short
I haven't dived into troubleshooting this except to drag out my sexy Chilton's schematics and find this is a very simple system. But taking it schematically to the actual car poses another problem.
Has anyone had a dead short that kills the tail lights? Is there a weak spot in the harness, or is it most likely the switch? If I put in a new 10A fuse, it will pop the second I pull the switch.
I did a search on the forum and didn't find anything on this topic. And I might be being just a little lazy to ask y'all first, but then again, if there's a trend of weak spots in the system, let's illuminate it (no pun intended, since it was such a bad one to begin with).
Has anyone had a dead short that kills the tail lights? Is there a weak spot in the harness, or is it most likely the switch? If I put in a new 10A fuse, it will pop the second I pull the switch.
I did a search on the forum and didn't find anything on this topic. And I might be being just a little lazy to ask y'all first, but then again, if there's a trend of weak spots in the system, let's illuminate it (no pun intended, since it was such a bad one to begin with).
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
I suspect that "sexy" Chilton's manual may have lead you astray. There's not much on these cars that's simple! You might find that book is good to use for TP. The FSM (Factory Shop/Service Manual) is soooo much better!
Does your Chilton's say anything about the front parking and marker lamps, the rear marker lamps, the license plate lamp, the radio and LCD instrument illumination, or the front cornering lamps (which are additionally controlled by the turn signal switch)?
I'd start by checking the easiest-to-access light bulbs. A corroded socket would be my first guess. As you check the bulbs, put a little di-electric grease on them.
If you don't have a big bucket of fuses, try this: Make a tester using an old headlight and a burned out fuse. Trim the top of the popped fuse a little so you can solder two wires to it. Wire the headlight to the fuse. Plug this into the offending fuse location. When you experience a short, the light will shine, but nothing will smoke! If there's no short, everything will work normally.
Does your Chilton's say anything about the front parking and marker lamps, the rear marker lamps, the license plate lamp, the radio and LCD instrument illumination, or the front cornering lamps (which are additionally controlled by the turn signal switch)?
I'd start by checking the easiest-to-access light bulbs. A corroded socket would be my first guess. As you check the bulbs, put a little di-electric grease on them.
If you don't have a big bucket of fuses, try this: Make a tester using an old headlight and a burned out fuse. Trim the top of the popped fuse a little so you can solder two wires to it. Wire the headlight to the fuse. Plug this into the offending fuse location. When you experience a short, the light will shine, but nothing will smoke! If there's no short, everything will work normally.
Last edited by Hot Rod Roy; Jan 27, 2015 at 03:30 PM.
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 249
From: Summerland B.C. Canada
Here is schematics from my 86 Factory service manual 
http://members.shaw.ca/dankai/Exterior%20Lights.pdf
http://members.shaw.ca/dankai/Exterior%20Lights.pdf
Thread Starter
Burning Brakes
Joined: Nov 2014
Posts: 936
Likes: 51
From: Post Falls ID
Bump
Started looking at things yesterday while listening to the Super Bowl, and didn't see anything out of whack that was easily seen...
Anyone had issues with the light switch itself?
All my marker lights are out as well, but the blinkers work.
Started looking at things yesterday while listening to the Super Bowl, and didn't see anything out of whack that was easily seen...
Anyone had issues with the light switch itself?
All my marker lights are out as well, but the blinkers work.
