Flickering lights?????

My Senior chief out here has a 76 cj, his lights will act normal for about 30 mins or so, and then they start to flicker after that. i have checked the usual, ground seems to be ok, light bulbs are fine, connection is good. im at a loss here and if i fix this for him its gonna give me some extra golf time away from work. any ideas guys

 

BOTH headlights? Dashlights? Parking lights?

I would guess it is the headlamp switch in the dash. It is pretty flimsy. After "ingesting" all of the salty air, it probably is about to give up the ghost.

BTW, are you involved with the USS San Fran? I have a friend onboard who I trained when we wrer on the Tucson out of Pearl.

 

sorry i should have shown more info. its the headlights, the only thing thats wierd is that he says it does after about 30 mins all the time. it never fails every time he turns on the lights they start flickering after sometime. i will check the switch though just to make sure..

i was not on the san fran, I am on the houston. i have several really close friends on the san fran though

 

how much does he drive it? could be that the charging system/ battery is going and after a bit of running without the lights it is charging up, but with the lights it can't handle the load. $ .02

 

Are you sure its only the headlights flickering. You might want to check the alternator out put. Measure the dc voltage coming out and then measure how much AC voltage is coming out of it with the headlights on and flickering. Anything over .15 vac and your alternator should be replaced. Sometimes one of the rectifying diodes goes bad and it will allow a little ac current out. The battery acts as a buffer in the electrical system so that may be why it takes a while to start flickering. If you can hook the alternator up to an oscilloscope and look at the voltage pattern that would be even better.

Don't know if this is your problem, but its another idea.

Kevo

 

Could be the voltage regulator going bad. I'm not sure how a stock CJ headlight circuit is supposed to be, but if it has a relay in it, the relay may be getting tired. The light switch itself could also be on it's way out. Ghetto Fab has some really good points as well

 

Had the same problem on my commando once,turned out to be the dimmer switch.
Dan

 

sounds like the circuit breaker is acting up which is built into the headlight switch
the harness connector which pushes onto the switch could also be melted/damaged from overheating
inspect it while you are there

 

I kind of aggree to with Dan.

Next time it starts flickering, might want to put a test light from the big lug on the back of alternator to see if it flickers. This is the wire that should also go to the battery. If it says bright, the problem is in one of the switches.

The dimmer or the headlight switch may still be ok. It might just be a lose contection of one of the wires. Tell him you need to get off and play some golf to think through all the possiblities. :>)

 

Is CDR Mark Benjamin your XO? He was the Engineer onboard the Tucson back in my time...

 

thanks for the responses i will check the switch and alt for him today, its funny you mentioned the golf thing to think about it, cause thats what i told him yesterday and by lunch i was on the course with some buddies drinkin cold beer and playing golf in the sun. i will let you know what i find out about the switch and alt. also he did say that its all his lights not just his headlights. im going with alt!


mark was my XO, now he is a commander and his stationed as a deputy for some adml. i know he screened for co and was going to be a skipper for one of the new boats

 

Remember, the headlight switch in the dash controls all of the lights on a Jeep too. If you look at an intermediate switch, it is really fragile looking: A piece of ceramic with a spring wrapped around it.

A $12 switch from 4WD might be the way to go instead of a new alternator. Try the troubleshooting methods mentioned and go from there.

 

will do, just to le tyou know this is a daily driver in guam, all the salt in the air out here is pretty bad on electronics. im guessing switch now that i think about it a little more. thanks for the help, im bringing my fluk into work tomorrow so we will se what i find out.