ruralandalone Posted June 8, 2019 Share Posted June 8, 2019 I am wiring up tail ights from scratch. What I can't be sure of is which light is where on the lense holder. Are the running and brake lights together with turn signal below, turn and brake above and running below, or some other arrangement? Link to comment Share on other sites More sharing options...
Ωhm Posted June 8, 2019 Share Posted June 8, 2019 Brake and Turn Signal share the same circuit. Both use the High Intensity side of the double filament bulb. The Low Intensity side of the bulb is for the parking lights. Link to comment Share on other sites More sharing options...
Eagle Posted June 8, 2019 Share Posted June 8, 2019 To expand on Ohm's answer: The Comanche, unlike the Cherokee, does not have turn signals that are separate from the brake lights. That may be why you are confused. Each side has two taillight bulbs. They both do triple duty -- the low intensity filament is the taillights (or what you refer to as the "running lights"), the high intensity filament is the brake lights AND the turn signals. And the hazard flashers. In operation, the turn signals override the brake lights, so if the brakes are on and you initiate a right turn signal, the right "brake" lights will flash while the left brake lights remain steady. If you activate the hazard flashers, the brake lights override the hazard flashers. This always seemed like an incredibly dumb arrangement to me, especially since AMC did it right on the Cherokee. This may help: https://comancheclub.com/applications/core/interface/file/attachment.php?id=14915 Link to comment Share on other sites More sharing options...
ruralandalone Posted June 9, 2019 Author Share Posted June 9, 2019 That helps. I think. The reason I am asking is even more odd. My truck bed is from a ranger. As are the lights. I have a dual bulb circuit on top (red lense), a single bulb circuit on the bottom (red lense). and a single bulb circuit in the middle(white lens). The last is clearly for backup, so what is the best way to wire up the others? The way it was wired up the turn signals and hazards worked, but keep blowing fuses on the running lights. So I figure either the wiring has a short (distinctly possible) or it is miss- wired. This ought to be simple, but I seem to be having a "senior's moment" in dealing with this.... To make matters worse, the wiring diagram shows a connector at the back to connect the wiring, but I have a plastic connection box which may or may not be original, and although the connections are labelled, if it is not original equipment it may not be labelled correctly..... At least the backup lights were reliable..... Link to comment Share on other sites More sharing options...
Ωhm Posted June 9, 2019 Share Posted June 9, 2019 Bulb question. Is your double filament bulb (upper) 1157? Is your single filament bulb (lower) 1156? Link to comment Share on other sites More sharing options...
ruralandalone Posted June 9, 2019 Author Share Posted June 9, 2019 I think so. I'll check it in the morning Link to comment Share on other sites More sharing options...
Eagle Posted June 9, 2019 Share Posted June 9, 2019 3 hours ago, ruralandalone said: That helps. I think. The reason I am asking is even more odd. My truck bed is from a ranger. As are the lights. I have a dual bulb circuit on top (red lense), a single bulb circuit on the bottom (red lense). and a single bulb circuit in the middle(white lens). The last is clearly for backup, so what is the best way to wire up the others? The way it was wired up the turn signals and hazards worked, but keep blowing fuses on the running lights. So I figure either the wiring has a short (distinctly possible) or it is miss- wired. This ought to be simple, but I seem to be having a "senior's moment" in dealing with this.... To make matters worse, the wiring diagram shows a connector at the back to connect the wiring, but I have a plastic connection box which may or may not be original, and although the connections are labelled, if it is not original equipment it may not be labelled correctly..... At least the backup lights were reliable..... Got a suggestion for you, if you can make it work. Download the electrical manual I gave you the link to. The rear lighting is on page 71. I have the Cherokee/Wagoneer electrical manual here. The Cherokee had separate, amber turn signals. The XJ Wagoneer was set up like the MJ, and I just confirmed that the wiring is the same. So ... how to get it to work like a Cherokee is the question of the day. The Cherokees and Wagoneers mostly shared the same chassis wiring harness - the stop and taillights were changed by a different section of harness just in the back. It should be possible to find a connector in the Comanche that corresponds to that, and make a custom taillight harness for the MJ that will give you separate turns and hazards. I'll see if I can scan the pages involved and post them tomorrow. Link to comment Share on other sites More sharing options...
Eagle Posted June 9, 2019 Share Posted June 9, 2019 I can't scan full-size pages. See if you can make out the photos. http://s39.photobucket.com/user/AguilaBlanca/media/Jeep Tech/Wagoneer_Stop-Turn-Backup_zpszv8x0thb.jpg.html http://s39.photobucket.com/user/AguilaBlanca/media/Jeep Tech/Cherokee_Turn-Stop_Backuo_zpsohl7tlud.jpg.html http://s39.photobucket.com/user/AguilaBlanca/media/Jeep Tech/DSC00143_zpsatoofcnk.jpg.html Link to comment Share on other sites More sharing options...
ruralandalone Posted June 9, 2019 Author Share Posted June 9, 2019 I can just manage the photos. Thanks for taking the effort to provide them. The dual bulb that is installed seems to be a 2057. Standard, dual filament, type. The bottom is a 1156. I can likely put one of the functions onto the lower bulbs and leave the other two on the top one. Not sure which would be the best arrangement. Or I suppose I could simply not use the bottom one at all, and use the top bulb for all 3 functions.... Link to comment Share on other sites More sharing options...
Eagle Posted June 9, 2019 Share Posted June 9, 2019 5 hours ago, ruralandalone said: I can just manage the photos. Thanks for taking the effort to provide them. The dual bulb that is installed seems to be a 2057. Standard, dual filament, type. The bottom is a 1156. I can likely put one of the functions onto the lower bulbs and leave the other two on the top one. Not sure which would be the best arrangement. Or I suppose I could simply not use the bottom one at all, and use the top bulb for all 3 functions.... IMHO it's more important to have redundancy for the brakes so, if you split the functions, use the upper set of two bulbs for the running light/brake function and the lower for turns and hazards. That's why the two uppers have two filaments and why the lower only has one filament. It's the right way to do it and, if you can figure out the wiring, I think it's worth the effort. Maybe someone on here who is scrapping a Cherokee could pull the rear lighting harness and send it to you. That might be a guide for how Jeep did it. Sorry the photos aren't better. My scanner only does 8-1/2 x 11. Maybe I'll try scanning to JPEG and using Paint to stitch the two halves of each page together. If I do that, I can also edit out the trailer light branch in the Cherokee diagram to make it easier to compare to the Comanche. Link to comment Share on other sites More sharing options...
Ωhm Posted June 9, 2019 Share Posted June 9, 2019 The 1156 is a high intensity filament. This bulb should parallel the high intensity filament of the 2057 (Brake/Turn Signal/Hazard). 16 hours ago, ruralandalone said: but I have a plastic connection box which may or may not be original, and although the connections are labelled, if it is not original equipment it may not be labelled correctly..... Do you plan on keeping this as part of the wiring? If so, why? Link to comment Share on other sites More sharing options...
ruralandalone Posted June 9, 2019 Author Share Posted June 9, 2019 Progress. Of a sort. 1) major short in light cable from rubbing on the frame. Now fixed. 2) The wiring for the second filament in the upper bulb disappeared in the wiring loom. Someone cut them off. I can replace them, but what should it be connected to? 3) With nothing connected to the terminals, I have identified ground, and the left/right signal wires, which also activate when the brakes or hazards work. SO far so good. 3) When the brakes or turn signals are activated, power is present (continuous) on another wire. Let's call this one "AUX". I cannot figure out the purpose, since I have a hot and ground already present for the turn & brake signal. Any ideas? I certainly can see duplicating the brake functions with the second (single function) bulb. That makes sense. And to answer the question above, I do intend to keep the junction box, as it provides a good waterproof connection. Link to comment Share on other sites More sharing options...
ruralandalone Posted June 9, 2019 Author Share Posted June 9, 2019 OK. got the "aux" figured out. It was the reverse power. So I have turn, brakes, reverse, hazards all working. The main problem is a fault in the running light wiring. Given the way the fuse blows, likely a direct short. Unfortunately I can't start to hunt for it until Wednesday. I only have two wires left at the rear, so I am hopeful that it will not be too hard to trace (assuming it is in the rear half of the running lights... It is a pity that the fuse block is in such an awkward spot. Link to comment Share on other sites More sharing options...
Eagle Posted June 10, 2019 Share Posted June 10, 2019 11 hours ago, ruralandalone said: I certainly can see duplicating the brake functions with the second (single function) bulb. That makes sense. The single filament bulb behind the red (or is it amber?) lens is the turn signal/hazard warning light. Or it should be -- that's the way it was wired in the Ranger. The problem is that the MJ factory wiring doesn't support that. However, as you can see from the wiring diagram, the MJ did use two bulbs on each side for brake/turn/hazard. If you don't want to modify the wiring to make it work as intended, just wire the single filament bulb to the high-intensity filament of the other bulb and you'll get redundant brake/turn/hazard lights. But, if you leave that as a single filament bulb, you won't have redundant running lights. By the way -- we'd like to see pics of the MJ with a Ranger bed on it. Link to comment Share on other sites More sharing options...
ruralandalone Posted June 10, 2019 Author Share Posted June 10, 2019 I can't get my head around leaving perfectly good lights unused. So I either double up on the brakes or the running lights. Both useful, but I think I will double the brake lights, since I do not plan to do much night driving with it. As far as pictures go, I will post a few when I get it out of the shop. It is definitely a "frankenjeep", as it has parts from several other vehicles on it, the ranger bed is a hydraulic dump box, and the bumpers are custom and massive.... Link to comment Share on other sites More sharing options...
Eagle Posted June 10, 2019 Share Posted June 10, 2019 2 hours ago, ruralandalone said: I can't get my head around leaving perfectly good lights unused. So I either double up on the brakes or the running lights. Both useful, but I think I will double the brake lights, since I do not plan to do much night driving with it. As far as pictures go, I will post a few when I get it out of the shop. It is definitely a "frankenjeep", as it has parts from several other vehicles on it, the ranger bed is a hydraulic dump box, and the bumpers are custom and massive.... Who said anything about leaving something unused? If that's what you got out of what we have posted, I think you're not reading the comments correctly. For clarification, how many bulbs does each of your taillights have -- three, or four? From your original post, I thought you had four -- two dual-filament bulbs behind a red section of lens, then a single filament bulb behind a white/clear section of lens, and then a single-filament bulb behind another red section. Whether you have one or two double-filament bulbs in the upper section, that or those was/were originally the tail ("running") lights and the brake lights. The one behind the white/clear lens is obviously the backup light. And the lone single-filament bulb at the bottom was originally the turn signal and hazard flasher bulb. If you're just typing into the existing Comanche wiring harness, that won't work so, as I posted above, you can use the bottom single-filament bulb as a second (or third) brake light. Link to comment Share on other sites More sharing options...
Jeep Driver Posted June 10, 2019 Share Posted June 10, 2019 41 minutes ago, Eagle said: Who said anything about leaving something unused? If that's what you got out of what we have posted, I think you're not reading the comments correctly. For clarification, how many bulbs does each of your taillights have -- three, or four? From your original post, I thought you had four -- two dual-filament bulbs behind a red section of lens, then a single filament bulb behind a white/clear section of lens, and then a single-filament bulb behind another red section. Whether you have one or two double-filament bulbs in the upper section, that or those was/were originally the tail ("running") lights and the brake lights. The one behind the white/clear lens is obviously the backup light. And the lone single-filament bulb at the bottom was originally the turn signal and hazard flasher bulb. If you're just typing into the existing Comanche wiring harness, that won't work so, as I posted above, you can use the bottom single-filament bulb as a second (or third) brake light. I'm not going to try to figure any of this out.......but......... He's using a Ford Ranger bed and tail light which has the amber turn......like the XJ.........here lies his confusion, how to separate the amber turn. Link to comment Share on other sites More sharing options...
Ωhm Posted June 10, 2019 Share Posted June 10, 2019 On 6/8/2019 at 8:20 PM, ruralandalone said: I have a dual bulb circuit on top (red lense), a single bulb circuit on the bottom (red lense). and a single bulb circuit in the middle(white lens). One (1) picture is worth a thousand (1000) keystrokes. On 6/8/2019 at 5:41 PM, ruralandalone said: I am wiring up tail ights from scratch. OP said he's rewiring. I can't tell where the MJ harness ends and the Ranger harness begins. Link to comment Share on other sites More sharing options...
Eagle Posted June 10, 2019 Share Posted June 10, 2019 3 hours ago, Jeep Driver said: I'm not going to try to figure any of this out.......but......... He's using a Ford Ranger bed and tail light which has the amber turn......like the XJ.........here lies his confusion, how to separate the amber turn. I know it's a Ranger bed and tailight. I assumed it was set up for separate turns/hazards, and I so stated a couple or three times. But he stated that both the upper and lower lenses are red -- no amber. And I also explained how to make it work with separate turns/hazards -- modify the MJ wiring to make it like the XJ Cherokee wiring. That's why I posted the Cherokee wiring diagram. Link to comment Share on other sites More sharing options...
Eagle Posted June 10, 2019 Share Posted June 10, 2019 I tried scanning the XJ stop/taillight diagram and splicing the two scans together. It's clear enough, but I couldn't get the two scans to stitch together perfectly. The important part for making an MJ work like an XJ is on the right hand side of the diagram. Let's see how this looks: Link to comment Share on other sites More sharing options...
Eagle Posted June 10, 2019 Share Posted June 10, 2019 Tried another scan. This includes the area where the XJ is different from the MJ: Link to comment Share on other sites More sharing options...
ruralandalone Posted June 10, 2019 Author Share Posted June 10, 2019 Got it. Two red lenses on each side. Double up the brake/ turn signals. I said "unused", because as it sits, only one filament of the dual filament bulb is wired up. This, to me, is stupid. More visibility is better. So I plan to wire it up again and make use of it. I am reluctant to wire all the way from the cab if I can avoid it, but if I do I will happily make use of the diagrams provided above, so thank you, Eagle, for posting those. I'm going to sleep on it while I figure out the **#&&$#$% short in the running lights. But my initial thought is to use the (currently unused) upper filament for running lights, and use the other two for the brake/turn/hazards... Link to comment Share on other sites More sharing options...
Eagle Posted June 11, 2019 Share Posted June 11, 2019 What you call the "running lights" (that's "taillights" to most of us) should be the lower brightness of the two filaments in the dual-filamant bulb. The single filament bulb should not, under any circumstances, be used for tailights -- it's too bright. The MJ tailights use two dual-filament bulbs on each side (plus a single filament bulb for the backup lights). If you don't need or want to split off the turn signals from the brakes/hazards, then you don't need my diagram. Use the diagram from the '88 MJ electrical manual, and just skip the second wire to the second bulb. Or change the sockets to dual filament and have complete redundancy on both sides. Link to comment Share on other sites More sharing options...
Ωhm Posted June 11, 2019 Share Posted June 11, 2019 35 minutes ago, Eagle said: Or change the sockets to dual filament and have complete redundancy on both sides. That's the way to go for the red lens. Replace both lower single filament with a dual filament and wire it just like the MJ. Low intensity bulbs for running/taillights, high intensity bulbs for (L/R) brake/turn/hazard. Link to comment Share on other sites More sharing options...
ruralandalone Posted June 11, 2019 Author Share Posted June 11, 2019 That is a good idea. I'll see if I can find a suitable socket. Link to comment Share on other sites More sharing options...
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