Taillights not working!

[ThisOldK10]

I am getting so frustrated. When I purchased the truck, all of the wires to the tails were cut and dangling. So i went ahead and spliced them all back together and I have no stop lights. I have lights when I pull the headlights but no blinkers, reverse or stop light. Its pretty dangerous and this is my only transportation so I need some help. I checked the fuses and bulbs. I looked at the "Tail lamp troubleshooting" thread but don't really understand.

 

[rich weyand]

Did you look for that cab ground? Yeah, this can be another of the symptoms.

Also, the lights in the back should have a ground to sheet metal from the light housing. The '83 has one on both sides. Make sure those connections are clean and intact.

More times than not, electrical problems on a vehicle are ground problems.

 

[ThisOldK10]

Did you look for that cab ground? Yeah, this can be another of the symptoms.

Also, the lights in the back should have a ground to sheet metal from the light housing. The '83 has one on both sides. Make sure those connections are clean and intact.

More times than not, electrical problems on a vehicle are ground problems.

I couldn't really see any grounds attached to the cab but the gauge issue came about suddenly when this has always been an issue.

 

[rich weyand]

You underestimate how screwy the electrics can get without a cab ground. Until you install that, you have no clue what you really have going on.

Also, check for those tail light housing grounds. Headlights too, while you're at it. One sheet metal ground on each side. That is, on your '83, the lights have a sheet metal ground at each corner of the vehicle.

 

[chengny]

If your parking lamps are lighting up (and I assume the license plate light and side markers are working as well) that would seem to indicate that you have sufficient ground capacity for the rear lighting harness.

Ignore the back-up lights for now. The problem is probably in the switch at the base of the steering column at the firewall - that can be dealt with later.

On the other hand, you really need to fix your directionals and brake lights.

The directional and brake lights share a common filament in the double filament lamp. They are controlled by a fairly involved set of contacts within the MFS (multi-function switch) in the steering column. The hazard lights are also involved:

You must be registered for see images attach

Don't mean to bum you out but, quite often the problem you describe is caused by the MFS - and the only solution is to tear the column apart and replace the switch. It is a pain in the ass job.

But before you even think about that, do some simple stuff.

Open the taillight assemblies and check that there is a dual filament bulb in the correct socket - the socket with two contact buttons.

Make sure the lamp is properly indexed within the socket (i.e. so that the lower pin on the bulb base is in the slot that goes deep down and the higher pin is in the other slot).

Make sure that the socket is free of oxidation.

Some more bad news:

To go any further with this diagnosis you are going to need a multimeter. And, you will need to know how to use it - at least enough to check for voltage and continuity.

Do those things and come back.

 

[ThisOldK10]

You underestimate how screwy the electrics can get without a cab ground. Until you install that, you have no clue what you really have going on.

Also, check for those tail light housing grounds. Headlights too, while you're at it. One sheet metal ground on each side. That is, on your '83, the lights have a sheet metal ground at each corner of the vehicle.

I'll check those grounds tonight.

If your parking lamps are lighting up (and I assume the license plate light and side markers are working as well) that would seem to indicate that you have sufficient ground capacity for the rear lighting harness.

Ignore the back-up lights for now. The problem is probably in the switch at the base of the steering column at the firewall - that can be dealt with later.

On the other hand, you really need to fix your directionals and brake lights.

The directional and brake lights share a common filament in the double filament lamp. They are controlled by a fairly involved set of contacts within the MFS (multi-function switch) in the steering column. The hazard lights are also involved:

You must be registered for see images attach

Don't mean to bum you out but, quite often the problem you describe is caused by the MFS - and the only solution is to tear the column apart and replace the switch. It is a pain in the ass job.

But before you even think about that, do some simple stuff.

Open the taillight assemblies and check that there is a dual filament bulb in the correct socket - the socket with two contact buttons.

Make sure the lamp is properly indexed within the socket (i.e. so that the lower pin on the bulb base is in the slot that goes deep down and the higher pin is in the other slot).

Make sure that the socket is free of oxidation.

Some more bad news:

To go any further with this diagnosis you are going to need a multimeter. And, you will need to know how to use it - at least enough to check for voltage and continuity.

Do those things and come back.

My MFS is actually gone on this column. Like just gone. Broken inside and everything. That would have an effect on the brake lights? I can piss people off all day with no indicators but my brake lights are a must fix.

 

[ThisOldK10]

Also, none of my running lights work EXCEPT for the tails. My front side markers dont even have bulbs in them and my front blinkers don't work and I'm not sure if that's a bulb thing but the housings are broken.

 

[GTME94]

My MFS is actually gone on this column. Like just gone. Broken inside and everything. That would have an effect on the brake lights? I can piss people off all day with no indicators but my brake lights are a must fix.

Yes, the power for the brake lights goes through the turn signal switch. My turn signal switch was broken and prevented the LH rear brake light from working. The brake and turn signal light uses the same filament of the rear bulb. If the brake light is not on, then the turn signal switch sends power to the proper bulb to make it blink. If you hit the brakes and turn on, say the LH turn signal, the RH brake light stays on constantly while the LH needs to blink. So the LH turn signal switch actually opens to brake the current coming from the brake light switch and makes the light blink. After you turn the corner and the turn signal cancels then the brake light stays on full time.

 

[ThisOldK10]

Yes, the power for the brake lights goes through the turn signal switch. My turn signal switch was broken and prevented the LH rear brake light from working. The brake and turn signal light uses the same filament of the rear bulb. If the brake light is not on, then the turn signal switch sends power to the proper bulb to make it blink. If you hit the brakes and turn on, say the LH turn signal, the RH brake light stays on constantly while the LH needs to blink. So the LH turn signal switch actually opens to brake the current coming from the brake light switch and makes the light blink. After you turn the corner and the turn signal cancels then the brake light stays on full time.

THANK YOU. You may have just solved my problem. I have a new MFS somewhere so I'll put that in and update you guys

 

[GTME94]

Is it the stalk or the actual switch inside?

Have you worked on a column before? 89Surburban did a good thread with visual instructions. You need a steering wheel puller and a lock plate tool.

 

[ThisOldK10]

I have not. And the stalk is broken off but the switch looks pretty messed up in tbere


Sent from my iPhone using Tapatalk

 

[hambo]

Did you ever end up getting the lights working? Im having sort of the same problem. I have no brake lights, just turn signals and the tailights. Maybe its my MFS switch. Any update?