Turn signals and hazard lights-1989 MJ

[Kenosha Warrior]

Ok, this is a mind-twiddler.

 

My turn signals are dim and flash at the same time, doesn't matter whcih side I flick the stalk to. but if I hit the 4way flasher button, all 4 are nice and bright and flash like normal.

 

what the hell is wrong?

[feerocknok]

Wires crossing somewhere? :dunno:

[Kenosha Warrior]

odd thing is, I had the bulbs out, reseating the taillights and when I was working on the floor, I smacked the 4way button on the column. Before then, the lights worked fine. now they won't. defective hazard flasher?

[JOMJ87]

maybe you shoeted out the relay on it??? Wouldnt hurt to check.

 

Cole

[Kenosha Warrior]

maybe you shoeted out the relay on it??? Wouldnt hurt to check.

 

Cole

pardon my ignorance, where should I look for that? I'm going to replace the hazard flasher if I can't find whatever else is wrong.

[JOMJ87]

I think its under the dash in the top of the fuse panel.IIRC I know for certain it wil make them act strange. My buddy had one go crazy on his YJ and they did some crazy stuff. Also if you change to LED bulbs you will possibly have issues with the relay.

 

Cole

[Kenosha Warrior]

I think its under the dash in the top of the fuse panel.IIRC I know for certain it wil make them act strange. My buddy had one go crazy on his YJ and they did some crazy stuff. Also if you change to LED bulbs you will possibly have issues with the relay.

 

Cole

 

I did replace the bulbs, but with the proper bulbs from the Haynes manual. there's this little metal rectangle, feels like lead, is kinda loose sitting on the bottom of my fuse panel, looks like someone kicked it reaching for the clutch. I'm going to replace the hzard flasher, Ive replaced all the fuses, and the one for the turn signals is in backwards, not that it should matter.

[feerocknok]

On my '86 it's on the fuse panel under the dash above the driver side kick panel. The top one is caution lights, the bottom is turn signals.

[Pete M]

So they started doing this after you installed new bulbs? You put double filiment bulbs in the taillights, yes? Somewhere in the back of my head I think I remember someone saying that the Haynes manual had a misprint on that. :dunno: But this is my memory so you never know. :roll:

[Kenosha Warrior]

the old bulbs still work, I just replaced them for the hell of it. The reverse lights are fine, and the tails come on nice and bright when I push the 4way flasher button on the column, but the front end is also flashing dimly when i throw on the turn signals, I never touched a thing on the front end in the way of lightbulbs.

[JOMJ87]

All the lights are kinda linked together thats why if you have one out that side flashes faster than it should. Maybe put the old bulbs back in just to rule that out.

 

Cole

[Wildman]

As others have said, Replace the flasher unit, at the fuse box, do both, and get the heavy duty type flasher, couple of bucks more. There both the same, and you can switch them to see if this helps the problem.

 

If you took the rear lights out, check the Ground at the drivers side, even replace the screw in a new spot, in the sheet metal, weak lights = bad ground, lights not working correctly = bad ground.

 

The worst thing is if you took out the bulbs in the rear, that one of the sockets might be bad, and back feeding thru the running lights, also the factory idea of wire conectors is not that great, just a crimp installed in the line and that could be corroded and = a bad connection.

 

Pete has mentioned before about the plug connector that on the drivers side, about 6-8 inchs in from the bumper, and this should be looked at also.

 

The back up lights are a totally diffrent circuit, and not tied into the stop lights or turn signals, and runs off a 7 amp fuse at the top of the fuse box,which took me 2 days to find. :headpop:

 

And yes the bulbs are wired kind of in series, so that if one bulb burns out, it will show in the guage cluster (turn signal) to let the driver know something is wrong.

 

And the rear tail light bulbs should be #1157, clear.

[Eagle]

And yes the bulbs are wired kind of in series, so that if one bulb burns out, it will show in the guage cluster (turn signal) to let the driver know something is wrong.

Not quite. They are wired in parallel, otherwise they wouldn't each be getting 12 volts.

 

What tells the indicator a bulb is burned out is the flasher. The standard flasher unit (if you don't have a tow package) is what's called a "load-sensing" type flasher. It's calibrated to flash at the normal rate when all the bulbs are pulling juice.

 

When a bulb burns out, the filament breaks and current no longer flows through that bulb. This changes the amount of current the flasher carries, which alters the flash rate. The opposite is if you connect a trailer to a standard flasher, it carries 50% more load -- that's why many times you'll see cars pulling U-Haul trailers with turn signals that flash very quick and short.

 

The heavy duty flashers used with tow packages are not load-sensing types. They are more durable, but they flash at the same rate whether you have four, six, eight, or just one bulb working. Which means if you run a heavy duty flasher (which I always do), you have to periodically check your turn signals and hazard lights because there won't be any indication of a burned out bulb on the dashboard.

[Wildman]

Eagle - Thanks for correcting me there, it is wired paralled, I'm doing too many door controllers, and there all wired in series, dry contacts.

 

And I didn't know that the flasher were in controll of the burned out bulb. Good info.

 

But I only replaced with heavy duty flasher units, just seams to solve problems, and I know that is what is needed for a trailer hook up.

[Kenosha Warrior]

you guys are awesome, my autoshop teacher also said check grounds and replace the flashers and it'll fix it, so thats whats on the plate this week :)

[Eagle]

Others have had similar symptoms, myself included. On the '88 MJ, the turns worked fine during daylight, but at night the left front parking light was dim, and the left turn indicator lamp on the dashboard always glowed when the lights were turned on. The problem was the typical bad ground in the parking light socket, causing the parking light filament in the bulb to seek a ground the only place it could find one -- by back-feeding through the turn signal circuit to the dashboard ground. I replaced the socket a few days ago. Tonight was the first time I've driven it at night since the repair, and the problem is GONE! No more glowing lights on the dashboard.

 

BTW -- let me stress that the bad ground is IN the socket, not in the ground wiring from the socket to the chassis. You can find a replacement socket at any of the parts chains. It won't say it's for a Cherokee/Comanche. I think the one that fits is for a Ford. Take your parking light housing into the store and match up a socket that fits.

[87manche]

I'll second Eagles comments, both of my front sockets were like that. Here's an easy way to see if thats it.

Pull the sockets

Then pull away the foam rubber gasket thing.

You'll see a channel that runs from front to back on the socket. Get an emery board and cut it down to fit in there. All I did to fix mine was grind off the corrosion, and fill the whole thing up with ox gard. Been fine for a year now.

The factory socket is a little stupid in that the ground is a flat piece of copper that touches a copper pin. There's not a lot of surface area to make that contact, so a little corrosion kills it.