Headlights problem on XJ 1992

Please, anyone can help me? Every time after about 30 minutes of driving with headlights on (even low beam only) they start flickering and then off, only parking lights stay. After one minute of waiting , i pull the switch again and lights are back till... this is driving me nuts. Headlamp switch is new, ''dimmer switch'' (high-low beam) is new, nothing wrong in lamps. Connection for headlights on headlamp switch (Tan colour wire) was little bit melted so I remove this jack and connected everything directly on place but problem is still there. I don't know where is ground connection for headlamps, maybe there is a problem. If anyone has any idea please help. Thanks Davey

Reply to
Davey
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Do you have aftermarket bulbs in the lights?

If the lights draw too many amps without a relay, they will blow a circuit breaker inside the headlight switch. Once this breaker has been popped, it doesn't ever hold full power after.

The main ground is a wire mesh strap from the engine head to the firewall.

If you follow the headlight wiring, at the end near one light you will find a black wire bolted to the fender or grill. This is the main ground.

The headlight switch has a ground wire under the dash near the steering column.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Davey wrote:

Reply to
Mike Romain

Reply to
Will Honea

The clue that I twigged on was "connection on headlamp switch (tan colour wire) was a little bit melted". Something made that connection hot, either over-load or corrosion. He says that he's replaced both the light switch and the headlamp dimmer switch, it would be good to know if this problem was the reason he changed out the switches or if there was something else going on. Either way it sounds like he's tripping the breaker, it doesn't seem likely that a bad ground is going to cause that.

Reply to
Lee Ayrton

I am thinking the same thing and I was implying once tripped, the breaker will never be stable again.

I was thinking he tripped the new one before he cleaned up the wires maybe?

Mike

Lee Ayrt>

Reply to
Mike Romain

I hadn't known that about automotive breakers, but I should have guessed, thanks for the tip. Regular AC breakers get weak if they get cycled, but it takes quite a few cycles to soften them up to the point that you'll notice.

Dunno. I'm hoping that he comes back and gives us more detail.

Reply to
Lee Ayrton

It takes a pile of heat to pop them, usually enough to melt things and the wires are 10 ga. so that is a serious draw.

Mike

Lee Ayrt>

Reply to
Mike Romain

Here I am. I 've just checked everything again and like Mike said, on left inner fender I found ground connections - three of them, little lower down just near left headlight - a bunch of connections and removed all of this, cleaned everything (with good old WD40) and tried to drive around almost half night. Nothing happened. Seems OK. Now I remember after one hard day for my rig somewhere in very muddy terrain I washed Jeep underneath and engine also (mud was everywhere), maybe some connections were corroded or, I don't know... I'll see next few days what will be but seems that everything is fine. One more question: This wire mesh strap which is hanging from firewall should be connected somewhere on cylinder head? I found it just hanging, not connected. Now it is temporary bolted on intake manifold. Probably previous owner forgot to connect again after doing some repairs. Seems to me like I can connect this back on bolt which holds fuel rail. I couldn't find any other ground connection from engine to chassis, strange. Anyway, thank you very much for advices, many greetings from far Croatia.

Reply to
Davey

Davey did pass the time by typing:

That's your engine ground strap. Without it your engine gets it's ground through the drivetrain and that can cause all sorts of sensor problems, rough idle, etc. It goes back to the block. On the 93ZJ it uses the same bolt that holds on the ignition coil, not sure about the 92 XJ.

Reply to
DougW

Holy crap!

Man you are some lucky, that ground strap is the main one for the body. It controls the lights and the ignition computer.

Your body tub was stealing ground from somewhere else which can happen, but normally when that strap goes, the engine dies and you have no headlights. I have seen gear shifts and gas pedal cables be the conductor... Also 2 way radios or stereos depending on their wiring.

That strap is supposed to go on the last head bolt, but if you have a good connection on the manifold, just leave it.

That might be all the trouble.

Mike

Davey wrote:

Reply to
Mike Romain

Guys, thanks a lot. Everything is fine now. This ground strap was a problem.

Reply to
Davey

Something else is bad. It happened again... I don't know what else to do.

Reply to
Davey

I found a culpret on my mom's old Grand Marquis, might be applicable. Seems the alternator connection was a little corroded and that was causing some AC on the voltage. Removed the connectors, cleaned them, and put them back. Probem went away.

Reply to
DougW

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