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jeepwrangler97 02-24-2012 04:28 AM

Electrical problems
So hopefully I am not to confusing since I am not mechanic and new to the jeep world for about a year. I bought a jeep since I have always wanted one and the jeep I bought was from a guy who obviously did a poor job taking care of the jeep. It has been running fine for about a year even though I drove it off and on for about 8mnths and only drove to school 4 days a week 10miles a day. I have replaced the spark plugs, air filter, o2 sensor and soon I will replace the fuel filter and oil. The problem I am having now is that its having electrical issues. It all started when check gauges started coming on a bit more and then eventually stayed on for a long period of time (used to just come on when I was coming to a stop after driving 40mph in the city.) Then one day at school it was dead, no power, just clicking noises coming from the engine when I tried turning her over(I seemed to have had power issues while driving right before I got to school.) So I bought a battery and that seem to have fixed the problem. After I left school the gauge went from reading 12v to 9v and thats when I found out at home that 12v is not good. Mind you I am only driving 5 miles to and from home so I am able to get there in one piece. Anyways I decided to change out the alternator brand new and replaced it myself. Problem still persised and it would run at 12v while driving then jump down to 9v. I thought the gauge was messed up so I started driving it around and thats when it finally died. I noticed right before it died that my lights were getting dim and dashboard to so I had to pull into mcdonalds where I tried jumping it with my girlfriends car. It has no problem getting jumped and will read 14v. I wanted to actually park it so I could tow it in the morning and it died again this time kicking, and the belt was squeeling, black smoke was coming out of the tailpipe which I am guessing because the motor was loosing power (Died twice in one night and 50 feet so I had to push her into a parking spot.) Next stop was to fix the corroded battery cables which I did. Hopefully I did it right.
-Universal pos and neg battery terminals and cables
-since the universal kit came with nothing I had to improvise
-cable going to fuse box is pos 10guage with a normal yellow assorted connection 10 gauge with the neg ground going to body also
-main pos cable goes to the bottom of engine along with fuse connection
-main neg cable is grounded to engine
-Had to make another neg ground since thread inside body broke
-I drilled a hole into the body next to air filter and ran a screw through another yellow assorted connection and a bolt is holding the screw in place. This is my neg ground wire I am guessing like in my neon its a neg ground screwed into the body
-pos terminal cable has 3 wires on universal, but only 2 on previous. I read somewhere the third could be hooked up from your stereo with a fuse of course.
-I cleaned all the sites since engine was dirty except neg ground to body is over paint. Old one was to, the firewall has paint on it as well. Neg ground to engine is cleaned though, it was very greasy
-Alt harness was dirty but I sprayed it with cleaner, its also rusted but I cant seem to buy that part anywhere, jeep dealerships do not carry 97 products, either does oreillys(schucks/checkers) or pep boys.
When my jeep is not completley dead it starts up great, its not cold outside or hot. I live in Az and its warm outside right now.
I did do a really stupid thing where I tried jumping the jeep with my other vehicle for a second without the battery connected to the jeep, I just wanted to see if the heater blower was working cause thats another problem of mine, but of course it wouldnt start/turn over(heater motor is right in front of the battery.) Check gauges was still coming on alot more before this but my gauge still read 14v. Apperently also the battery I had just bought had a bad connection and wasnt sending singles correctly within the battery, and thats when I had to replace it this week since they couldnt charge it. They said running it dry would not cause the inside of the battery tray to break. Replacing the battery still did not help my situation and I still go from 12v to 9v after driving down the road about a block or 2.
-again first problem I fixed was new battery
-after all these problems that I tried fixing like alt and cables I tried charging battery so I could get the jeep to our new house, thats when I noticed the portable battery charger kept reading check.
-I went back to pep boys and got a new battery that tested good this time
-problem is still going on after all that I did and I am confused, maybe I F'd something up
-one guy did mention something with the regulator
Sorry for the long description but my situation is off the wall and I am trying to be precise. 97 tj wrangler se, 2.5l 4cyl softtop, 33bfgs.

Indy 02-24-2012 06:18 AM

Your voltage regulator might be bad. Stupid thing is that it is built inside the ECU. Read the following thread, has a bunch of information ... Hope this helps.

jeepjones 02-24-2012 06:19 AM

Oh my, you certainly have quite a few issues going on don't you. Without actually seeing your repairs it is hard to know if you've done everything correctly so I'll start out with some basic things you can check to get you going in the right direction. First, I'd move this post to the "Electrical" section of the forum, that way more of the electrical wizards would see it. Other than that I would advise you to get those codes checked the next time your check engine light stays on that way you can start figuring out what making it come on. Did you get the alternator checked? What's it's output? As for the grounds, they should be going to the frame not just the tub, the tub is mounted to the frame with rubber bushings and rubber is an insulator as well as there are more than a few. Check all of your wiring to make sure everything was done correctly.

jeepjones 02-24-2012 06:43 AM

Check your PM box I sent you a link that will help you figure out your problem.

TnDz TJ 02-24-2012 07:09 AM

Sounds like the voltage regulator in the ECU.... I second that.....

jeepwrangler97 02-24-2012 05:16 PM

Took me all night just to figure out how to post, but I will try to move it. Thank you guys for all the help, after I am done with all this I will be able to actually help other people lol. I will check out the manual I was told about and then check my wiring, and regulator/ECU. Thanks again!! I just really want to drive her again, I havent even been able to get her off the road and it sucks.......soo much work to do

jeepwrangler97 02-24-2012 06:18 PM

This pic is pos main cable and fuse box cable hooked to what I am guessing is the starter at the bottom of the jeep, the old cables were connected by rubber so I had to cut the fuse box cable from the old pos cable
This is where the main neg cable is mounted to the engine, I cleaned with engine cleaner
This next pic is where the second "ground" or whatever from pos cable goes to fuse box with a regular yellow connector, top wire is the fuse wire that connects to bottom of jeep and its old and crappy but cant find part, same with alt harness
Next pic is where I made my own ground to tub, not firewall
This i why I had to make a new ground for neg cable because, the thread inside firewall broke off and bolt will not come out
This is my battery terminals and rest of connection, I still do not know where the third pos cable goes to since there was only 2 cables on old pos cable, 3rd cable you cant see but its black

jeepwrangler97 02-24-2012 06:20 PM

again my alt is 2 weeks old but I have not tested it since I do not want to remove it again, plus I just installed it and I am hoping its not broken yet. Hopefully this helps, thank you again

jeepwrangler97 02-17-2013 02:50 AM

The problem was the distribution center and PCM. I took the jeep to a dealership and they fixed most of the problem after 1200$. Problem still persists and I took it back, but to start with the issue was somewhat the PCM for anyone that has this problem.

jeepwrangler97 11-02-2013 07:10 PM

Again PCM was faulty the dealership put in, PCM and jeep run great! Just updating because this was a pain in the butt issue.

jeepwrangler97 11-02-2013 07:11 PM


Originally Posted by jeepwrangler97 (Post 5846010)
Again PCM was faulty the dealership put in, PCM and jeep run great! Just updating because this was a pain in the butt issue.

lol PCM was replaced and faulty, they had to order new PCM and no issues in over 6 months.

Water Dog 11-02-2013 07:25 PM

The PCM is where the voltage regulator lives.

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