Hello all, this is my first post.....
I have a 1990 1/2 ton blazer. All of the lights work, except the tail lights. I read about dash lights and tail lights combined going out. This one seems different. I have no tail lights, unless I have the truck in reverse. My brake lights work. My interior lights sometimes work. My dash lights always work. My turn signals, slow, but always work. I had a little time, while at work. Oh yeah. License plate very dim. I checked the voltage at the trailer wiring, got about 2v. Any suggestions? I'm thinking its probably a ground? PS. It has what appears to be a Reese 4 way Trailer Hitch Wiring Light Kit installed in the harness. I haven't had a chance to do that yet. I might before I go to bed.

 

Pulled the trailer harness inspected all the connections down there. All looked good.

 

The harness was been spliced with butt connectors and has bad grounds. Anybody want to come over?

 

Ran new ground from the battery. Same results. Noticed dome lights will not come on at all anymore.

 

Check your hazard lights switch, I know you and I have totally different vehicles but I was having the same problems as you and I finally started messing with the hazard lights switch and found that if i applied pressure to the left the brake lights would work, and if i applied pressure to the right they would cease to work. Its probably not the answer but its worth a try.

 

Your problem is most likely in the tail light harness connector in the back. These plugs usually rot and break a wire. I have had to rewire many Chevrolet trucks with new harness plugs.

 

Is it repairable, or do I need to order one?

 

For a simple test, couldn't I run a hot jumper to the splices in the wire (from back forward) and then to headlight switch and the splices at the brown connector and see if they come on? Then I should know about where the problem is right?

 

Been busy. I hate working 77+ hrs a week... Don't know if its related or not but tonight, on my way home, my headlights didnt want to come on. Don't know why, but after turning them on/off repeatedly they came on. The switch is new installed, last Thursday (1/6).

 

you're right, your truck (which is more similar to a 2nd gen Blazer than the older K -series) is totally different.


@ nktidwel: glad that things are working for you again.

but one thing i didn't see in all of your posts, was that you were ttracing the wires front to back, checking for a break or a grounding out issue. seems kinda weird that a switch replaced a week ago, has now started making things work correctly. i'm think you need to check the wiring from the HL switch all the way to the TL's. 'cause i'm pretty sure the real issue hasn't gone away.


that's the only thing that sucks about Winter, messing around with all that snow/salt/dirt crammed up into the deepest reaches of the undercarriage.