Electrical Issues

Sounds like a short circuit, whether it be from a wire shorting out through the insulation onto something metal or a melted circuit on a circuit board.

Quote from JMack

I've had some small electrical gremlins in the TJ for a while now, but they generally kept to themselves and didn't cause any issues that were too concerning. Over the weekend though they came out to play and now I've got some odd issues that I could use some help with.

When I hit the brakes or put on my right turn signal (yes, only the right one), the clock on the radio turns off, radio it self isn't affected and when I take my foot off the brake the clock returns. When I turn the headlights on, the cigarette lighter doesn't work.

I'm not very experienced at troubleshooting electrical issues, so any advice here is appreciated.

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IIRC, the clock on your stereo is fed by a constant hot that allows your stereo clock to keep the correct time and also allows the stereo to retain memory such as presets, equalizer settings, etc. The rest of the stereo should be only powered when the ignition is on or the key on ACC. The turn signals work the same.. when the key is on.. but brakes should work independent of the ignition sequence. My first thought would be an issue pointing towards the ignition switch. I can't really think of a common ground between those components other than the ignition switch.

As for the headlights/cig lighter, I'm not sure how they share anything in common and I don't have any TJ knowledge about them. In my YJ, the headlights are run through the switch, independtly from anything in the ignition circuit. My cig lighter is powered off of the ignition switch.

I'd look at the ground on your right tail light assembly - specifically, where the 3 bolts ground the light housing to the tub. Check for corrosion sandwiched between the tub and the housing, under the head of the bolts where they contact the plate in the light housing, and where the threads of the bolts make contact in the holes of the tub holding it all in place. Those light housings are known to lose their ground connection and that will make things act in very unusual ways. Maybe you are losing ground there when you tap the brakes, hit the blinker, or turn on the parking lights and the system is searching for a ground in another location that has unswitched power (i.e. clock, cigarette lighter, etc). If you're already looking at the right side, might as well check the left side housing too. The nice part is you only need a small Phillips to pull the lens cover off and I think a 10mm or 13mm socket to remove the 3 bolts - a few minutes work at worst. Good luck.

If I remember correctly, Erica's TJ was once having some seriously wonky issues that ended up being all solved by cleaning up the ground connection at one of her tail light housings.

Listen to chris. Tail light ground issues cause all kinds of crap to go wrong. Check the simple things first.

Quote from astape

Listen to chris. Tail light ground issues cause all kinds of crap to go wrong. Check the simple things first.

X3 check the grounds at the tail light.

Glad you got it figured out.

Check all of your bulbs.... If one is out or has corroded terminals it could cause it to blink fast. Additionally I've chased intermittent lighting issues for hours and realized it was all caused by a bad turn signal switch on the column. A little jiggle here and there and signals would come and go. Brake lights wouldwork when they felt like it. I've replaced about 4 of them on various tjs and xjs

Quote from JMack

Yes and no. Most problems solved, new one found. My blinkers are blinking at a very high rate of speed. Everything seems to be working, lights are flashing, just faster than normal. Have to look at that this weekend.

That could just be the flasher relay going bad. Cheap and easy replacement.

Have you replaced the multifunction switch? I'm on my third. When they go they cause all kinds of weird issues like what you describe. ~$40 part and 15 min to swap

Quote from Kuntryboy816

That could just be the flasher relay going bad. Cheap and easy replacement.

Maybe. The flasher relay in a WJ is about $80. I'm not sure a TJ but that's not cheap. I took the cover off of one and soldered it back together.

They all have a multi function switch, it's part of the turn signal in the stalk.

The multi function switch is just a fancier name for the turn signal switch that I mentioned a few posts back. It functions your left and right turn signal, high and low beam and it has the Hazzard switch on top.

Flasher relays work off of the heat they build up running the lights. They come on, heat up in a certain amount of time, And turn off. If there is more resistance or more load, they work faster. As Ed said, corrosion on the bulbs or any terminals or grounds could be the culprit. The loose terminal you mentioned could also be the cause. For blade terminals you can fold up a tiny piece of 400 grit sandpaper to clean the contact surfaces, and squeeze them down a little tighter with pliers before adding some dielectric silicone grease and plugging it back together. Corroded bulbs can be cleaned up the same way. One time I had an 1157 bulb (2 filaments) got put in not quite all the way and the bulb was contacting both contacts at once, causing weird stuff. Also check that the hazard light switch is all the way in or out, that can mess stuff up too.