Electric Short

[AZpathy25]

Hey everyone been following this for a while but this will be my first post.

 

I have a 95 pathy. I was driving home last Friday and had an electric short in my front left clearance light wire. The lights were missing when I bought it and the wire were just hanging. I'm not sure if my tires rubbed on the wire or how they split open. Anyways I had a short that roasted the wire and fuse in the tail lamp spot. I was able to get the front quarter panel off to have a look at the wiring harness and a good foot and a half of it were all melted so I just cut it out. My big question is does anyone have any experience in replacing a section of the wiring harness and have any good tips?

 

I will try to get some pictures up when I get home. I also have checked the car over for other issues. I was not getting any power to my crank sensor and checked back to my ECU. The lights were not coming on so I already have another one coming in from Ebay. Should I check for something else to be shorted out. I've done the most I can with my little experience in electrical work. I am fairly good with wiring as I have installed a lot of stereos in my day and feel comfortable with hooking wires up.

 

I would really like to get some advice of how to proceed as I have a little time before the new ECU comes in.

 

Thanks

 

[Slartibartfast]

Index of /FSM/Pathfinder <Download the '95 manual, and get friendly with the EL section.

 

I would look for faults at the computer before swapping it out. Computer failures in these are not common (if you don't count guys driving into ponds and flooding them out) and plugging a new component into the place of a blown one without figuring out why the old one blew sounds like a good way to blow the new one, and if it turns out the problem isn't the computer, a new computer won't change anything. I'd start by just making sure the thing is getting power and ground.

 

Surprising that a shorted marker light burned up the wires before the fuse went. Did the PO plug in a bigger one when the dangling wires kept shorting and popping the fuse that was supposed to be there? Or was it one of those crap Harbor Freight fuses where the plastic will melt long before the fuse actually blows?

Looks like in your avatar pic the passenger's side marker is missing. Is that the one that shorted? IIRC most of the engine control stuff is in that harness, too, so perhaps the damaged corner light wiring bridged to the wiring for something more important. Did the ECU stop working at the same time the fuse blew?

[AZpathy25]

Index of /FSM/Pathfinder <Download the '95 manual, and get friendly with the EL section.

 

I would look for faults at the computer before swapping it out. Computer failures in these are not common (if you don't count guys driving into ponds and flooding them out) and plugging a new component into the place of a blown one without figuring out why the old one blew sounds like a good way to blow the new one, and if it turns out the problem isn't the computer, a new computer won't change anything. I'd start by just making sure the thing is getting power and ground.

 

Surprising that a shorted marker light burned up the wires before the fuse went. Did the PO plug in a bigger one when the dangling wires kept shorting and popping the fuse that was supposed to be there? Or was it one of those crap Harbor Freight fuses where the plastic will melt long before the fuse actually blows?

 

Looks like in your avatar pic the passenger's side marker is missing. Is that the one that shorted? IIRC most of the engine control stuff is in that harness, too, so perhaps the damaged corner light wiring bridged to the wiring for something more important. Did the ECU stop working at the same time the fuse blew?

It was the driver side that shorted out and the passenger may have had some issues. I remember a little puff of smoke on that side when I had the hood up and turned my lights back on to try to locate the short. The fuse had to be a cheapo because it definitely melted before it blew. It was actually a smaller fuse than was supposed to be there. I have the service manual and it was supposed to be a 15A and I had a 10A. It was the tail lamp fuse. It was the only one that blew. I pulled all of the others and I can't tell if any relay may have gone or not.

 

After the short I pulled over and tried to figure out what it was in a parking lot. I had to leave it over night and came back the next day with a test light, fuses and some wire. The engine would turn over but it wouldn't fire. I went to o reilly and got an ignition module just in case it seemed to be the best option at the time. I pulled a plug and when it turned over I wasn't getting spark but there was definitely fuel going in. So I know the injectors were getting power. I followed the power back and the ignition module was getting power but nothing was coming out. I installed the new one with no luck. My next check was the crank sensor. It was not getting power with the key on or starting. After looking around online it seems the sensor goes straight to the ECM. I went back to check it out and looked at the green and red lights on the back side and with the key on I wasn't getting any light so I am just guessing it is blown from that.

 

I am currently working to replace the part of the harness that I know is bad because the wires melted everything around them in the section under the quarter panel. My next goal is to go over to the other side and check them out because of that little puff. I am supposed to have the new ECM by Friday and Ill have all the wiring done by then and then ill try out the new ECM and hope it will fix the issue.

[vagabond]

it's basically one loom from the headlights to the taillights, separate looms for the engine and dash rear hatch and fuel tank and center console.

I upated my 88 to 95 electrical which was a major job. hopefully you can splice in the bad section. if it's burnt all the way to the fuse panel your in for a major job