98 rear tail lamp and ABS light problem

[Headnsouth]

My 98 (165k) has recently shown me a problem that I'm not sure where to start. While driving the ABS light will come on at any time and when you apply the brakes the directional dash indicators will both light up. After reading something about the rear tail light circuit boards being flukey I pulled them and noticed the center terminal was melted. But whats causing this problem?? Is it the circuit boards?

[LMP]

Water/moistrure intrusion in tail lights clusters of this model is a common problem with various effects. My brother had his (Montana) changed while the car was still on warranty. I have no idea though of the relation with ABS....possibly the rear sensors use the same ground return circuitry as the tail lights and in case of cluster failure it fools the sensors ...but that is just an hypothesis, not a statement.

[Headnsouth]

The whole area is dry as a bone so I don't think moisture is a problem. Its most likely the circuit boards that are causing the problem. I just hate to shell out $43 bucks a pop for something that might work.

[LMP]

I thought about it a little more and reread your original message and here is what happens: there is a ground return problem for the rear light clusters, posssibly a broken path in the circuit board as you describe: when you apply brake, current goes through brake lamps then having no place to go to ground, enters the direction light from the ground side (ungrounded) , exits at the normal hot side that is tied to the indicators in the dash, and possibly ends up lighting also the front direction lights . THis is a very old problem...remember having had similar situation with several cars of various vintages.

It is probable you can solder a ground bypass in the light cluster(s) to replace the damaged track....or if the ground is not broken at that place, follow the ground path as long as it is good and splice to a good conductor to a known valid ground.

[Headnsouth]

I pulled both of the tail light assemblies last night and the drivers side ground (plug in) connector melted the surrounding plastic a bit. Cleaned the terminals with a scotch brite and removed the female side of the terminal and repositioned the contact points. Applied a electrical contact enhancer and it seemed to stop the problem. I'll know more as the vehicle get used today. :fingersx:
I'll have to look for a new molded connectors to replace the damaged one. I also really need to check the ground to the chassis but didn't have time to remove the trim.