Rooster92

Right now I just reconnected it. I am ordering a replacement connector.

I reattached the connector by the battery (the relay harness) to the post on the starter relay. The connector that I said was still in bad shape is the one behind the left headlamp. Thank you for all your tips!

As for the solid blinker... thank you for the tip!

The issue is solved and it has nothing to do with that corroded connector. It turns out, the PO had installed a headlight relay harness. The eyelet where it connects to the starter relay had broken and was disconnected. I had noticed this thing in the engine bay, not knowing what it was at all. I was reading about them here and recognized the picture. Once I reconnected it the headlights came on. The relay harness was tucked there next to the battery this whole time. I got lucky again this time, but that connector is still in terrible shape. Part of me wants to let sleeping dogs lie for fear of causing more damage. Either way, I am going to order a replacement. https://www.amazon.com/Newdeli-Waterproof-Electrical-Automotive-Connectors/dp/B0C5MBSDW2/ref=sr_1_18?keywords=Deutsch&qid=1703281506&sr=8-18&th=1

Now that the truck is starting up, I am addressing the headlight and turn signal issues. The headlights won't turn on at all. The turn signals are intermittent. Sometimes they don't work at all. When they do, one side (left) is ony a solid light. The right side will blink. After reading the @cruiser54 tips, I thought I would start with the connector behind the left headlamp. Right away I find a problem. Some of the pins have broken off entirely. I am looking up how to replace this. There is not a lot of slack in the wire. Any advice is welcome. Once this is fixed I am going to check out the headlight switch itself and add a headlight relay harness. Oh yeah, and the ballast resistor was broken.

I am happy to report that she is now running. Once I re-installed the switch, she started right up! Thank you to everyone that helped me on this thread, especially @Ωhm. Those diagrams you sent were huge.

I do not believe there is an issue with the SR. Since the wire is continuous from the IGN switch all the way to the SR, I figured the issue must be on the battery side. There is no power flowing from the IGN switch to the SR. This schematic shows the red wire going from the IGN switch to the SR, and then from there it goes to the battery. As it turns out, that is continous as well. So, we have a continous wire from the battery, to the SR, to the IGN switch. We also have a continuous wire from the IGN switch to the IGN terminal on the SR. All that is left is to connect the two. So I went ahead and jumped it. Once I connected the red to green, the engine turned. As I understand it, that only leaves one possible point of failure: The IGN switch. Like I said earlier, I replaced that aready. So, its either a bad switch out of the box (unlikely) OR I installed it incorrectly (much more likely). Either way, I am going to step away from it until tomorrow.

I got a positive continuity check on both 5 and Ground.

Honestly, I believe that the terminals on the SR are mislabled. That is why my wires appeared to be backwards on the original picture I took. I also saw a video on youtube of a guy working on an XJ... he mentions something similar around the 4:10 mark. https://youtu.be/baU6_wBkk8k

Yes. Also, connected + straight to G. That engaged the starter motor as well.

I removed the wire from the "I" terminal. Then I connected a jumper cable from the bare "I" terminal on the SR to the + terminal on the battery.

When I connected the IGN relay terminal straight to the positive end of the battery, nothing happened. I then took the same jumper cable and connected the solenoid wire straight to the positive end of the battery. The starter motor engaged.

D2 4 does show voltage with the key turned

Where is that located?

You are correct. I have no idea how that could have happened. Also, I have been testing each of those wires to confirm which one goes to the ignition. I have connected them one by one to a multimeter while turning the key. The sad news is... none of them had a jump in voltage when I tried to crank the engine. Not good.

Oh good, its on sale!

Okay, so I am still scratching my head over this no crank/no start issue. Here are the things I have ruled out: - Battery is not dead - Starter motor/solenoid are not broken - Ignition switch is most likely not broken (brand new) - Engine is not seized I have been trying to trace wires in order to find any that are broken or damaged. Other than the blown link I already addressed, I haven't found anything. I BELIEVE I have identified the ignition wire. There are two green wires that come out of the starter relay. One is going off to the left and one is going off to the right. The one on the right goes to the starter motor. The one on the left I believe is coming from the ignition switch. My reasoning is that I know there is a green wire coming from the ignition switch, and it makes sense if it is the same color as the one going to the starter motor. Right now, the only thing that I can't confirm is working is the starter relay itself. After all, fuses don't burn out on their own. The problem is, a new one is $50. I can't return it if I install it in the vehicle. Does anyone know of a way I can test if it is functioning correctly?

I replaced the fusible link. Now, the clock and radio will turn on! As for the engine, it is not cranking. At least there is some progress.

Awesome, thank you.

Thank you. What is the difference between the starter relay and the starter solenoid?

Okay, so I have just been staring at my engine bay and trying to trace wires with my Haynes manual. The colors are not matching. I noticed that a fusible link is completely blown. I don't know what it goes to or what the rating is. Also, just to make sure, this is the starter relay, correct? (The metal box at the top of the picture, where a bunch of wires are terminating)

Okay, so I am starting to do some back-tracking.... As I said I have had the truck sitting for quite a while so I am trying to remember exactly what happened. 1. One day I was driving it in the late afternoon. I realized as it started to get dark, the headlights wouldn't turn on. 2. The next day, it stalled out on me while I was driving it. I coasted to the side of the road. I do remember trying to start the engine, but it wouldnt catch. At that point, it would still turn. I ended up getting it towed. 3. Because of the headlight issues the previous day, I decided it must be the alternator. I took the alternator out and got it tested at an auto parts store. They told me it was still working well. 4. After putting the alternator back in, nothing happens when I turn the key. Well, except a buzzing sound. As I said, I have checked the battery and starter motor as well. It seems like I made the problem worse when I took the alternator out and put it back in. I did visibly check to make sure it was in correctly. Now, I am going to retrace my steps with the alternator.

Well, the battery cables did have some tears in the jacket. I replaced those and it did nothing. I also finished replacing the ignition switch, and that also did not do the trick

It will not engage.

Bottom line up front... My Comanche will not start, neither the engine or the accessories. About a year ago, the truck stopped running while I was driving. I tried to restart the engine with no luck. I have confirmed that the battery, alternator, and starter motor are all good and functioning normally. Also, I understand that the clutch master cylinder is above the fuse box. There is no evidence that it is leaking. Also, all the fuses are good. My next course of action is to replace the ignition switch. I am in the process now. I did notice some heat damage on one of the connectors. Unfortunately, my Comanche has been sitting for a while. I haven't been able to address any of the issues due to work and life. Any advice on the situation is much appreciated. Thank you.