About a month ago I replaced my alternator after not being able to start the truck and having my voltage meter spike intermittently while driving. I also had the interior and head lights flickering at night. As soon as I turned the engine off it killed everything (except the under hood work light for some reason) and had be jumped. I realized shortly after that the heads on the battery cables would need to be replaced because there was a bad negative connection. In the mean time, I zip tied the negative cables in place and everything worked fine for about 3 weeks. Last week, the truck wouldnt start, and I couldnt get a good connection on the negative, so I replaced the heads and still have the same issue. I really cant figure anything except that the battery might be shot, but I'm not sure why that would explain the voltage spikes and flickering lights after im running. Going to test the battery after work, will update. I'm not very electrically inclined so any help would be appreciated. Thanks!

Info- '00 XJ 4.0 I6 Sport
Alternator- Autozone stock replacement special
Also just recently installed KC Daylighters which required taking the corroded heads off the battery which is where this all stems from..

 

First thing you need to do is take your battery in and have it charged and load tested. A constant discharging and recharging is bad for a car battery unless it's a deep cycle battery. You also need to check all of your grounding point. Also check you battery cables not just the ends. Take the battery cable and give them a bend. If you hear any crunching sound you should replace them. And check you connections again on the alternator and clean the connection to you starter.
This should keep you busy for a little while. Hopefully it will take care of you problem.
keep us updated if it helps or not.

 

I feel like I been down that road...also feel like my roto had something to do with it....or cps lol ....7$ or 95$...ill get back to u....also nss....damn I had alot of problems all at once..in anycase, I had that problem and I'll update to let u know how to fix it )

 

Rotor...check it out, takes 2 seconds

 

NSS can be intermittent. Several good posts here, just did that. Check the circuitry, kinda hard to find diagrams and seems to be year-specific. Some say to manually cross via safety pin the B and C wires (on my 98 these were black and brown/yellow) - if that solves issue, then it is a great hint that its your NSS. Not starting? When you energize the ign switch - does everything else (interior lights, radio, etc)? When my NSS fried, as I turned the switch to energize starter, everything went dead, came back on in accy position. Try jostling shifter handle or starting in neutral? Mine was intermittent - start it up, drive 5 mins and turn off - wouldn't start for fifteen or twenty minutes, then fine. If you started and ran it more than ten minutes, the NSS was not a problem, started right up again. Kinda frustrating. If you want to pull it and clean it out, be careful. I don't off road, opened mine up and it seemed clean and OK, though the contacts did look like they needed polishing, broke mine getting it off to "fix" it. Stellar, huh?

 

http//bc4x4.com/tech/2010/jeep-neutral-safety-switch-nss/

Great link for removal and cleaning of nss very thorough

 

Corrected link (those darn colons...):

http://bc4x4.com/tech/2010/jeep-neut...ty-switch-nss/

And yes, this is an excellent link for the NSS. There are also several guys who have done this on the forum and posted info. Thanks Reddskie.

 

Yesssir, I edited that link like 3 times, then gave up figuring someone might take pitty on me lol...i have used this link and it helped me greatly, took me 45 min works excellant !!

 

Short Update- Because of the snow storm/ my heavy work schedule, I haven't been able to get the battery load tested, (I'm going to switch batterys with a buddy of mine after work today to check). I did check the grounds and battery cables. But now I have a new problem, not sure if it chages anything as to what you guys have thought previously. I jumped the battery after work last night during the snow storm, and as I was driving, on two occasions the power shut almost all the way down for about 3 seconds, dimming all the interior/ exterior lights, but it didnt feel like the truck was shutting down. I got it home and this morning I jumped with my buddy's jeep, and left it running for about 15 mins while I got ready for work. I went out, put in Drive and it shut down. Then I jumped it with my brothers car, and as soon as I took the positive cable off the battery it shut down. I tried several ways of trying to get it to run, but no matter what I did, as soon as the positive cable was off it died. I really appreciate the help and I'll try to update later if the new battery works, but it seems like a deeper problem at this point..

 

Check ur rotor under the distributor cap, if its broken all that will happen

 

DO NOT pull off the battery cables when the vehicle when it is running! You can fry the computer system and end up with bigger problems.

 

I was under the impression he was talking about the jumper cables not the actual positive cable

 

I'm suspicious of the VOLTAGE REGULATOR .....
Erratic, unregulated output could account for

Go some place and get them to test Battery and Charging System, might cost you $15 - $35 but might save you from throwing a lot of $$$$ at other hard parts.



BROKEN ROTOR / DIST CAP ---- Should cause RANDOM MISFIRE engine codes ...... at least that was the symptom I got when I have a problem there.



.

 

I forgot to ask if any codes came up our if light was on?

 

Hey there gents,

Just so you know, I replaced the battery and everything worked fine, I believe that the issue must have stemmed from cycling the battery all the time when I had to continually jump it. Thanks for the help, on to bigger and better problems, like flushing the heater core this weekend!! haha Happy Thanksgiving all!