Smoke coming from steering column

[vfb]

I have a 1989 Comanche 4 L. The other day I was driving along and noticed some smoke coming out of the steering column, specifically right around the turn signal. It stopped the smoke after about 20 seconds, but occasionally it starts up again. I’ve checked the wires as much as I can underneath but can’t see anything obvious. I’d like to have a look inside the steering column but can’t see how to remove it to get at the wiring.

Please suggest how I should proceed now. Don’t want to have a fire!,

thanks

[89 MJ]

You would probably have to pull the steering wheel and then the turn signal switch to be able to inspect everything. I have had this same thing if some oil gets spilled on the exhaust manifold. The smoke can travel up the column and out the turn signal hole. 

[vfb]

Thanks for that. I’ll check to see if it’s oil but I’m thinking that would probably be more consistent or regular. I’d need a steering wheel puller to get it off ,right?  Too bad you can’t just take the plastic cover off

[89 MJ]

You are correct, you will need a puller. You can typically rent them from parts stores if you don't have one. 

[vfb]

Ok, I’m willing to get a puller and try taking the steering wheel off but after that how to proceed?  Will I need to disassemble the whole column?  Is it likely that it’s the turn signal wiring?  And how did you discover the oil drip onto the exhaust?  I don’t see any evidence of oil underneath and have spent quite a while looking at the wires under the dash but still can’t see anything burnt or melted. 
The smoke still happens but only for short periods and very inconsistent and doesn’t seem to be related to anything. I’m guessing eventually something will short out or catch fire so I’m nervous about it. 
 

thanks from a non mechanical guy!

[AZJeff]

The steering column has electrical switches attached to it for the turn signals and the ignition switch.

 

The turn signals are up at the top, right under the steering wheel.  The steering column in your MJ was made by General Motors, so any writeup on how to disassemble a GM column would apply.    Pages onwards through 4 of the following write-up should explain how to gain access to the turn signal switch in that type of column:

GM column disassembly

 

The ignition switch is on the top of the column down near the brake pedal, and it's easiest to drop the column to work on that piece.

[vfb]

Thanks for that link. It looks more involved than I hoped but if I can get the puller and lock plate remover I might give it try.  Probably I’ll spend more time looking/hoping for a bad connection under the dash since I won’t be able to get those tools till later next week. 

[Ωhm]

Disconnect C158. Determine if SMOKE goes away. If yes, problem could be C267 or C268. C267_A is a known issue.

 

 

 

[vfb]

Sorry, I’m having trouble figuring out what you mean by C158. Is that on the diagram you posted?

 

 The only way to tell if it’s gone will be to drive lots I guess,  because the smoke is very sporadic (once or twice on a 20 minute drive) and short lived (15 seconds at most)

[Ωhm]

4 minutes ago, vfb said:

Sorry, I’m having trouble figuring out what you mean by C158. Is that on the diagram you posted?

 

C158 refers to the connector number. Photo shows that connector with pin callouts and location.

[vfb]

I guess I’d better go look again and maybe it’ll make more sense. Serious lack of knowledge and experience with vehicles here🙄. 

[89 MJ]

36 minutes ago, vfb said:

I guess I’d better go look again and maybe it’ll make more sense. Serious lack of knowledge and experience with vehicles here🙄. 

Everybody starts somewhere, you’ll learn more with time

[vfb]

24 minutes ago, 89 MJ said:

Everybody starts somewhere, you’ll learn more with time

Thanks for the encouragement I just learned that the C158 connecter is in the back of the cab under the carpet (under the seat I guess). Not a project for today! I was just out for a 20 minute drive and everything was perfectly normal. So, a bit encouraging ……. until it happens again

[Ωhm]

1 hour ago, vfb said:

I just learned that the C158 connecter is in the back of the cab under the carpet

 

Thanks for help keeping me straight. I meant C156, not C158. Ignore C158 in my statements. 

[vfb]

2 hours ago, Ωhm said:

 

Thanks for help keeping me straight. I meant C156, not C158. Ignore C158 in my statements. 

Glad you caught that!  It’s easier to get to now that I know