swsws1 Posted March 28, 2014 Share Posted March 28, 2014 OK 86 my mj had a rear lighting problem so I took out the spliced and diced taillight harness and replaced it with an un-molested one from the JY. Now it starts and runs and all the rear lighting works except for the running lights when the headlights are on the turn signals brake lights and reverse lights all work but for some reason the dash lights and tail lights are inop the fuse is not blown Iv checked and rechecked. I imagine if it were the headlight switch itself then headlights and forward running lights would work either. If anyone has any idea what's going on please help me out. Link to comment Share on other sites More sharing options...
cruiser54 Posted March 29, 2014 Share Posted March 29, 2014 My head hurts from reading that. From a teacher -- short and to the point In the world of hi-tech gadgetry, I've noticed that more and more people who send text messages and emails have long forgotten the art of capital letters. For those of you who fall into this category, please take note of the following statement: "Capitalization is the difference between helping your Uncle Jack off a horse and helping your uncle jack off a horse." Is everybody clear on that? Link to comment Share on other sites More sharing options...
FrankTheDog Posted March 29, 2014 Share Posted March 29, 2014 Lol Link to comment Share on other sites More sharing options...
cruiser54 Posted March 29, 2014 Share Posted March 29, 2014 Lol True,eh? Link to comment Share on other sites More sharing options...
Eagle Posted March 29, 2014 Share Posted March 29, 2014 In the world of hi-tech gadgetry, I've noticed that more and more people who send text messages and emails have long forgotten the art of capital letters. And punctuation ... such as periods and commas. I recently read that using periods in text messages is considered insulting. No wonder people can't communicate any more. [/sermon] Did you splice in the new tail harness, or did you plug it in at a factory junction connector? Link to comment Share on other sites More sharing options...
FrankTheDog Posted March 29, 2014 Share Posted March 29, 2014 Lol True,eh? Yes, very true. In the world of hi-tech gadgetry, I've noticed that more and more people who send text messages and emails have long forgotten the art of capital letters. And punctuation ... such as periods and commas. I recently read that using periods in text messages is considered insulting. No wonder people can't communicate any more. [/sermon] Did you splice in the new tail harness, or did you plug it in at a factory junction connector? I must insult a lot of people with my texts because I try to use proper spelling, punctuation and grammar. It's to easy to get complacent and lose what little I have. Link to comment Share on other sites More sharing options...
NHMJXJ Posted March 29, 2014 Share Posted March 29, 2014 That's great! I'm still laughing! Link to comment Share on other sites More sharing options...
yxmj Posted March 29, 2014 Share Posted March 29, 2014 My head hurts from reading that. From a teacher -- short and to the point In the world of hi-tech gadgetry, I've noticed that more and more people who send text messages and emails have long forgotten the art of capital letters. For those of you who fall into this category, please take note of the following statement: "Capitalization is the difference between helping your Uncle Jack off a horse and helping your uncle jack off a horse." Is everybody clear on that? :rotf: My aunt Jill owns a stud farm.......from this day forward I will re-read her messages very closely when she invites me over to help her..... :rotfl2: Link to comment Share on other sites More sharing options...
gogmorgo Posted March 29, 2014 Share Posted March 29, 2014 As you may have gleaned from the comments above, we're not quite sure what's happening, because we're not quite sure what's going on. So your MJ had a sketchy taillight harness. You replaced it with one from a junk yard. How did you attach it, did you cut and splice or did you unplug the connector and swap the whole thing, bulb sockets and everything? Did it come from another Comanche? The Cherokee ones aren't the same. Now your rear running lights don't work. Neither do your dash lights. Everything else does, though. What works when the headlights are on? What works when they're off? We're not sure. The headlight switch does a lot of things, but it has only three positions: Off. The switch is pushed in all the way. No lights should be on. Parking. The switch is pulled out to the first stop. Dash lights should come on, as should the parking lights and the side marker lights in the front. Taillights also come on. Headlights. Same as parking, just with headlights on. Which positions are you having trouble with? Here's a wiring diagram of the headlight switch itself, might help you out a bit. The colours may not reflect the colours of your wiring, but it should be the same circuits. The fact that your dash lights aren't working tells me that there could be an issue at the headlight switch. The headlight switch is the only place they're tied in to the rest of the harness. I'm assuming you know how to turn the headlight knob to dim/brighten the dash lights. The connectors for the headlight switch like to melt. Mine straight up set itself on fire not all that long ago. If it did melt, something could easily be shorted in there, causing all kinds of problems. Installing an upgraded headlight harness with relays is more than just a good idea, taking the load off the headlight switch and keeping everything cool and not liquid. If everything was working before the new taillight harness, though, it's unlikely that swapping it triggered anything. But we're not sure what all's going on. We do want to help, but it's hard to help when we don't know what's going on. I'd also point out that the tail light harness could have been hacked apart to "correct" the issue you're seeing, and that the rewiring made things work with what was there rather than properly fixing an issue. Typically with an electrical issue, you should start at the source of the electricity, and work your way "downstream" to make sure everything's hunky-dory. If you start the other way, you might end up "fixing" an issue that isn't actually an issue, it's just not working properly because there's something funky going on upstream. The power for the parking lights starts at the fuse, then goes into the switch. After the switch, it splits and goes between the front/rear, and also the wire that triggers the clock brightening/dimming. Link to comment Share on other sites More sharing options...
swsws1 Posted March 29, 2014 Author Share Posted March 29, 2014 OK sorry for my poor description of what's happening. What's going on is the turn signals, brake lights and reverse lights all work correctly however when I turn the headlights on the rear running lights and dash lights don't come on. The headlights and front running lights come on but no rears. I have checked the fuse and I went to the junk yard and got a complete un-spliced taillight harness and still no rear running lights or dash lights. I just now and I mean JUST now replaced the headlight switch itself. I hate to ask this because I would much rather fix it correctly but is there a way jump a constant wire Into the taillight harness just to get the tail lights to work. Its a 500$ truck so I'm not too worried about resale value. Link to comment Share on other sites More sharing options...
Eagle Posted March 29, 2014 Share Posted March 29, 2014 OK sorry for my poor description of what's happening. What's going on is the turn signals, brake lights and reverse lights all work correctly however when I turn the headlights on the rear running lights and dash lights don't come on. The headlights and front running lights come on but no rears. What happens when the switch is in the parking lights position (halfway out)? I have checked the fuse and I went to the junk yard and got a complete un-spliced taillight harness and still no rear running lights or dash lights. But where and how did you tap the new rear harness into the vehicle wiring? Did you get a Comanche harness or a Cherokee harness? Did you remove your old harness at a factory connector and just plug in the "new" harness, or did you cut and splice to make te connections? I just now and I mean JUST now replaced the headlight switch itself. I hate to ask this because I would much rather fix it correctly but is there a way jump a constant wire Into the taillight harness just to get the tail lights to work. Its a 500$ truck so I'm not too worried about resale value. Do the dash lights function when the headlight switch is in the parking light position? Do you know that rotating the knob of the headlight switch is the dimmer, and that if the knob is rotated all the way it turns off the instrument lights? Link to comment Share on other sites More sharing options...
swsws1 Posted March 29, 2014 Author Share Posted March 29, 2014 When the switch is in the parking light position the forward running lights function correctly but the rears and dash lights are still inop. I got the harness off of a Comanche and cut it off the Doner vehicle around the fuel tank so I would also get a new plug as well because the original was beat to hell. When I spliced it into the the truck I'm trying to fix I cut the plug off and spliced in the new harness. So really I have a bit more harness than I really need. And the dash lights are inop no matter which way the headlight knob is turned. Link to comment Share on other sites More sharing options...
swsws1 Posted March 29, 2014 Author Share Posted March 29, 2014 I just wanna get it fixed so I can sell it and work on the barn find eliminator. Link to comment Share on other sites More sharing options...
dave92cherokee Posted March 30, 2014 Share Posted March 30, 2014 When doing all this work did you check and clean that ground point behind the drivers side light? That crappy ground is notorious for causing weird problems. Link to comment Share on other sites More sharing options...
MJCARENA Posted March 30, 2014 Share Posted March 30, 2014 Have you checked the bulbs to make sure they are good. When I got my truck only one dash bulb was good,the rest were burned out. Link to comment Share on other sites More sharing options...
swsws1 Posted March 30, 2014 Author Share Posted March 30, 2014 I cleaned the ground up very well and cut the old ground tag off and put a new shiny one on. The bulbs are all good Link to comment Share on other sites More sharing options...
benjy_26 Posted March 31, 2014 Share Posted March 31, 2014 I got tired of this type of issue with "new" jy harnesses. I finally just bought some spools of wire, connectors, and ran my own harness. Problem solved. Link to comment Share on other sites More sharing options...
Eagle Posted March 31, 2014 Share Posted March 31, 2014 When the switch is in the parking light position the forward running lights function correctly but the rears and dash lights are still inop. I got the harness off of a Comanche and cut it off the Doner vehicle around the fuel tank so I would also get a new plug as well because the original was beat to hell. When I spliced it into the the truck I'm trying to fix I cut the plug off and spliced in the new harness. So really I have a bit more harness than I really need. And the dash lights are inop no matter which way the headlight knob is turned. Okay, so you wanted to splice rather than just use a factory plug. Your call -- I didn't see the original. When you spliced, are you certain you matched all the wire colors correctly? Did you solder the splices, or just twist the wires together and wrap with electrical tape? Since you have a plug in the rear harness, pull the plug, identify which wire feeds the rear taillights, and check that wire on the forward (body) connector of the plug to verify whether or not you're getting power that far. If so, you then focus on wiring from the connector back. If not, the problem is forward of the connector. Link to comment Share on other sites More sharing options...
swsws1 Posted March 31, 2014 Author Share Posted March 31, 2014 FIXED!!! It all works I found the corroded culprit right under the driver seat area. Thanks a lot for everyone's help. This is my first MJ Iv had 2 xjs and a fleet of V8 Dakotas. But seriously thanks guys. I'm most likely going to need more help here soon with the barn find eliminator. Link to comment Share on other sites More sharing options...
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