84' Suburban I'm driving at night and headlights go off and back on again.

[justaburbn]

I'm driving, it's dark out, and all of a sudden my headlights shut off and then back on again. They are probably only off for a second or two and then back on again for a while. Talk about living dangerously!

This could be caused by any number of things. I'm not sure were to start. Has anyone ever had this happen and what might be the most common cause?

I guess I'm going to have to buy some kind of amp meter/tester. Any suggestions for a good one?

Thanks,

[justaburbn]

So... I think I know why my headlights are shutting off on me. I was driving my 91' Suburban after rebuilding the tilt wheel steering column. I replaced all the electrical switches, including the turn signal lever with cruise control while I was at it. This all started because of the inherent issue with those doggone bolts down in there that always come loose because the factory doesn't apply any lock tight on them. You get to do that yourself when the tilt column gets all wobbly floppsy and you cant take it anymore.

I made 2 mistakes when rebuilding.
1. I didn't replace the steering shaft universal joint. There is still some movement in the reassembled column and I'm guessing that's it. It looked good to me, but stupid is as stupid does. I can't wait for that part to come so I can take it all apart again.
2. I used a grease that was too thick (don't ask me why) on the plastic part that contacts the column shroud/housing. This plastic part is that goofy piece between the turn signal lever and push rod that engages the dimmer switch. Also that push rod might be bent or binding on something. It's cold out here in winter so that grease and or rod or both are not allowing the rod to move freely and easily and so there is a drag on the rod that wont allow the dimmer switch to just click on and off quickly. This I believe (on my 91') is causing the headlights to shut off mid way though it's otherwise quick and rapid movement.

This all leads me to believe my 84' Suburban has a bad dimmer switch, hopefully.

Now guess what? The 84' Suburban has a tilt wheel steering column that is all wobbly floppsy too! And yep, oh joy, I get to rebuild that one as well.

But first, I will buy a new dimmer switch for the 84'. If I can just reach up under the dash and unplug it I can plug the new one in and manually engage the dimmer switch (you know, like by hand when it is just hanging there) to see if that in fact is the issue. If I can't get to the switch to remove the plug without breaking the 40 year old thing, then I'll have to drop the whole column.

On another note; One thing I don't understand is why the original wiring needs to be replaced sometimes, like especially when it comes to slow windows and such. I just don't get that. Another day, another topic if I can't solve this one, I guess.

[kwmech]

Hi-lo switch or a cracked fuse

[Accelo]

Headlights are not fused. They are on a breaker that is built into the head light switch. Before condemning the column you may try changing out the light switch. These breakers sometimes fail. But mostly the lights going on and off is because the breaker is resetting its self, because of an overload condition. Cheers.

[v30crewcab]

there is also a fuseable link off the starter that is a power wire for the headlights. its a black or white thing on the wire. I've had those get a loose connection internally and cause the lights to go on and off.