jazzyjeeper Posted August 26, 2022 Share Posted August 26, 2022 Hi all, last I posted my truck had been stolen, and miraculously it made its way back to me, nearly unscathed. Dealing with my insurance was such a drawn out nightmare that I never posted an update about finding it. When I got it back it wasn't starting, and a shop diagnosed it as a fuel pump issue. They noted some electrical stuff that had been tampered with but after they replaced the fuel pump it was starting so they just made a note to see an electrician if issues arose. Well since then, I've been driving it for about three months, and I've had a few issues. Not sure if this is related or not. So yeah, the other night I went to drive home and my headlights wouldn't turn on. No brights either, but turn signals work. The dash is dark, except turn arrows when I hit those. The instrument gauges do work. I read other headlight threads and checked/cleaned my headlight wiring harness, replaced all my fuse box fuses except for the 7.5's, and replaced the headlight switch. When I rotate the headlight switch I do get the light by the kick panel so it's doing something. I am stumped. Does this also mean my rear/brake lights are out? Am I a doof and it's one of the 7.5 fuses? I bought a mixed box of em and got home and realized there weren't any of that amperage. I have a continuity tester but am new to electrical stuff. Any tips appreciated!! Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 26, 2022 Share Posted August 26, 2022 Have you checked all your fuses? Sounds like it could just simply be a blown fuse. Also congrats on getting your MJ back! Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 9 minutes ago, eaglescout526 said: Have you checked all your fuses? Sounds like it could just simply be a blown fuse. I replaced all of them except the Transmission and Gauges fuses unless I'm missing any? The fuse box in the kick panel is the only fuse location on the 89 right? Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 26, 2022 Share Posted August 26, 2022 Yes it is. Trans fuse if yours is a manual controls only the reverse lights and nothing else. Gauge fuse does what it does and that’s the gauges. Check that one just to be safe but I don’t think AMC wired the lights into that circuit. Have you checked for power at the headlamp switch? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 4 minutes ago, eaglescout526 said: Yes it is. Trans fuse if yours is a manual controls only the reverse lights and nothing else. Gauge fuse does what it does and that’s the gauges. Check that one just to be safe but I don’t think AMC wired the lights into that circuit. Have you checked for power at the headlamp switch? I haven't checked for power at the headlamp switch, would I need to probe the switch harness to do that? Oof it was not fun getting in there! Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 26, 2022 Share Posted August 26, 2022 Yes you would need to. But I think you should be able to probe the fuse too just to see if there is power there. Chances are there probably is power there. If not then there’s something between the fuse block and the battery that’s not sending power to the head lamps. Speaking of power to head lamps, have you added one of those relay harnesses yet to your MJ? Link to comment Share on other sites More sharing options...
Pete M Posted August 26, 2022 Share Posted August 26, 2022 sounds like it's time to pull the harness off the headlight switch and inspect for melting too. checking all the high-amp connectors is part of regular maintenance on our old trucks. (hvac, steering column, blower motor, blower resistor pack, etc) Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 22 minutes ago, eaglescout526 said: Yes you would need to. But I think you should be able to probe the fuse too just to see if there is power there. Chances are there probably is power there. If not then there’s something between the fuse block and the battery that’s not sending power to the head lamps. Speaking of power to head lamps, have you added one of those relay harnesses yet to your MJ? Ok. Just took another look, I replaced the fuses with the easyID fuses today to make things easier for me, and didn't see any indicator lights just now. And no, I haven't done the relay harness upgrade yet. 18 minutes ago, Pete M said: sounds like it's time to pull the harness off the headlight switch and inspect for melting too. checking all the high-amp connectors is part of regular maintenance on our old trucks. (hvac, steering column, blower motor, blower resistor pack, etc) When I replaced the switch I tried to see if there were any signs of damage- it was pretty up there in the dash but from what I could tell I didn't see any melting. I cleaned it with some electrical cleaner and greased it up when I plugged the new switch in. Thanks both for your tips! I hope I can figure it out but starting to think I might need an expert to step in - in person. Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 26, 2022 Share Posted August 26, 2022 Have you looked at the electrical manual yet? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 30 minutes ago, eaglescout526 said: Have you looked at the electrical manual yet? I just looked, trying to understand the headlamp troubleshooting table- so does Fuse Link J connect at the starter relay? And the rest of the terminals described are in the headlight harness? 1 hour ago, eaglescout526 said: Yes you would need to. But I think you should be able to probe the fuse too just to see if there is power there. Chances are there probably is power there. If not then there’s something between the fuse block and the battery that’s not sending power to the head lamps. Speaking of power to head lamps, have you added one of those relay harnesses yet to your MJ? Just realized the easyID fuses will only tell me if the fuse is blown, not if there's no power Will check! Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 26, 2022 Share Posted August 26, 2022 Yes. All the fusible links meet at the starter relay for power. There could be possible corrosion there as well Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 Checked my fuses, there is no power on the Flash to pass fuse, Hz/stop, Park LPS, and INST LPS. I looked at the starter relay, didn't see anything that jumped out as being damaged or corroded. I replaced the starter relay about 9 months ago. What I did probe there lit up but I wasn't sure which one was link J. The fusible links are pretty crowded so I didn't get a direct prod at everything. Link to comment Share on other sites More sharing options...
Pete M Posted August 26, 2022 Share Posted August 26, 2022 do you hear a clicking noise further down the column when you engage the brights? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 1 hour ago, Pete M said: do you hear a clicking noise further down the column when you engage the brights? I don't. The only noise I hear is right where the signal lever meets the column, when I release it back into place there is a click. The brights don't turn on when I do this and the lever doesn't stay in the brights on position. Was trying to think of an event that may have caused this, could it be related to braking since the brake lights are also out? I did really slam on the brakes a few days ago which I don't usually do. Could that have upset the brake light switch and triggered the other issues? Link to comment Share on other sites More sharing options...
Pete M Posted August 26, 2022 Share Posted August 26, 2022 confirm that the rod that runs from the multifunction stalk down the column to the hibeam switch is there and engaging the switch. I've had them get out of alignment before. you can also check for power there. @cruiser54 any ideas? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 26, 2022 Author Share Posted August 26, 2022 6 minutes ago, Pete M said: confirm that the rod that runs from the multifunction stalk down the column to the hibeam switch is there and engaging the switch. I've had them get out of alignment before. you can also check for power there. Just stuck my head under and it is engaging the switch. Link to comment Share on other sites More sharing options...
gogmorgo Posted August 26, 2022 Share Posted August 26, 2022 Did they mention what electrical things had been tampered with? I'm kinda wondering if they didn't somehow take power from the headlight circuit to jump to the ignition and whatever they did there caused an issue. It's definitely the wrong way to hotwire if that's the case, but there's no guarantee the thieves knew what they were doing, and the fact you got the truck back relatively intact suggests they weren't in it to make money off the truck or out for a joyride which would make me think it's not something they do often, i.e. not the most competent thieves. The 7.5 amp gauges fuse also supplies ignition power to the headlamp delay module if you've got it, which theoretically could be causing some kind of issue, but I don't really see it completely disabling the headlights, or pulling power to other circuits. The headlight switch only switches the ground side of the interior light circuit. The interior lights coming on when you turn it only means the dome circuit is getting power. This is good because it means that there's at least some current going through fuse link J. But it doesn't tell us if there's power to the headlight switch. It also adds some element of confusion though in that the power feed through the fuse panel for the Dome circuit is also what feeds the HZ/stop and park fuses, and the headlamp circuit is fed power from a splice point in that same circuit prior to the fuse panel. The Inst lmp fuse gets power from the headlight switch so I'm betting once you resolve the headlamp power issue the instrument lamps will be resolved as well. I can't remember off the top of my head where the circuit breaker for the headlights is, but it would be worth checking if that had power. Then I'd be taking a closer look at the fuse panel. I've never had it happen to me, but I've been warned against using too much dielectric grease on a connector such as the one for the headlight switch, because it can interfere with the connection. I'm just looking at the '88 wiring manual in the DIY master thread at this point. Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 28, 2022 Author Share Posted August 28, 2022 On 8/26/2022 at 3:13 PM, gogmorgo said: Did they mention what electrical things had been tampered with? They didn't. Not sure if this offers any clues but security camera footage showed the guy driving off within 15 minutes of getting inside. They also got my club off somehow so they didn't spend too much time with it, whatever they did. Maybe I'll post a picture looking up into the kick panel area because there are a few dangling wires. It's always been a mess in there. On 8/26/2022 at 3:13 PM, gogmorgo said: I can't remember off the top of my head where the circuit breaker for the headlights is, but it would be worth checking if that had power. Then I'd be taking a closer look at the fuse panel. I'm not finding any info on the circuit breaker, anyone know where that would be? Going to try again and test for power at the harnesses this time. Will also check the ground on the driver side headlight. Any other grounds I should look for? The switch harness and headlight harness should be hot at all times, right? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 28, 2022 Author Share Posted August 28, 2022 Maybe I should have started here... the red and white wires near the center go nowhere, and the yellow toward the upper right has been snipped. Also I don't like that black box hanging down like that, where is that supposed to be secured? Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 28, 2022 Author Share Posted August 28, 2022 On 8/25/2022 at 8:54 PM, eaglescout526 said: Yes you would need to. But I think you should be able to probe the fuse too just to see if there is power there. Chances are there probably is power there. If not then there’s something between the fuse block and the battery that’s not sending power to the head lamps. Speaking of power to head lamps, have you added one of those relay harnesses yet to your MJ? I probed the headlight switch harness, and there was only power at terminal D. This was with the truck off- is that the correct way of testing? Also probed the headlight harness with the switch on, truck off, and no power there. I probed the fuses the other day and there was no power to the Flash to pass fuse, Hz/stop, Park LPS, and INST LPS. So it should be something between the fuse box and battery as you said? What should I look for there? Thanks again for any advice, even with the electrical manual in front of me I am not sure how to troubleshoot as electrical stuff is new to me Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 29, 2022 Share Posted August 29, 2022 Is yours an automatic or a manual? If it’s a manual, suspect corrosion damage to some terminals or terminals that have failed. By chance, what other lights come on? Like cluster lights, side markers. Link to comment Share on other sites More sharing options...
jazzyjeeper Posted August 29, 2022 Author Share Posted August 29, 2022 18 minutes ago, eaglescout526 said: Is yours an automatic or a manual? If it’s a manual, suspect corrosion damage to some terminals or terminals that have failed. By chance, what other lights come on? Like cluster lights, side markers. It's a manual. Thanks, will check out the terminals. Lights that I'm seeing come on are the brake indicator and arrows for the turn signals in the dash, and front and rear side markers. No running lights, brake lights, or headlights. Link to comment Share on other sites More sharing options...
eaglescout526 Posted August 29, 2022 Share Posted August 29, 2022 I would suspect the fuse block suffered corrosion damage. You might have to pull the block out as far as you can and see what’s going on behind it. Or pull the suspected fuse out and see what the terminal looks like. It could be something simple that the terminal has fallen apart or no longer exists. Link to comment Share on other sites More sharing options...
Sb7908 Posted September 1, 2022 Share Posted September 1, 2022 I am having a similar issue and it appears as though the terminal for the dash lights is corroded. I’m a total newbie to all this so can’t be sure. How does one replace a terminal on a fuse block? Or would it be safer to attempt to replace the dash bulbs before messing with the block? Link to comment Share on other sites More sharing options...
Pete M Posted September 2, 2022 Share Posted September 2, 2022 On 9/1/2022 at 1:16 AM, Sb7908 said: I am having a similar issue and it appears as though the terminal for the dash lights is corroded. I’m a total newbie to all this so can’t be sure. How does one replace a terminal on a fuse block? Or would it be safer to attempt to replace the dash bulbs before messing with the block? a few guys here have repined the entire block. not sure if there's an official writeup though? check the DIY subforum. Link to comment Share on other sites More sharing options...
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