Hi I'm new to this website. Hope I can get some help. I have a 1995 jeep cherokee country with 210,000 miles that I've owned for 13 yrs now. I am having a very anoyying and frustrating voltage drop of about 2 volts when I have my heat and headlights on at the same time and then continues to drop. I've changed and checked everything I could think of and it still does it. It's fine when I first start it. Reads just above 14 volts where it's always been but after a little while it starts to drop slowly. If I turn my heat on it drops more then if I have my headlights on it really dumps. If I turn everything off it comes back up some but not where it usually was. I have a new 880 CCA battery and 200 amp alternator. Gutted the interior and checked all wires. Checked all fuses and replaced all relays I could find. Cleaned what grounds I could find inside and under the hood. Bought a new headlight wiring harness with relays and replaced the blower motor and the volt gauge still drops. The only after market stuff I have on the car is my 800 watt amp for my stereo, a 32" Cree led light bar and my auxiliary fan on a manual switch inside my jeep. I'm about to rip out what little hair I have left. Can someone please help me. And yes I've had the battery and alternator checked. Said both were working fine and no codes popped up either. What could still be causing the voltage loss? Can someone please help me? I don't know what to do. Thanks.

 

Ever done a ground refreshing? Sounds to me like one has rotted away.

BTW this is more an OEM Tech question than pertaining to actual electronics.

 

I still have all the original ground wires under the hood. Maybe I'll try that but when I had the battery and the alternator tested they tested fine. Yeah I didn't realize that till after I posted this. I did post this again in the OEM Tech section. Thanks for your suggestion.

 

That won't show a ground problem, and most shops have no clue about ground issues.

 

"having" them is usually the problem lol, I'm not sure where you are but corrosion and vibration kill everything.

Now that I'm not on my phone I found this a little easier. It's written to the previous model of XJ, but all of the concepts - and some of the locations - are the same. https://www.cherokeeforum.com/f51/cr...x-tips-153657/ See posts concerning ground and connector refreshing. Hopefully the issue is not inside the cab, but maybe the headlight grounds.

All kinds of interesting things happen in these vehicles when grounds aren't right. My personal favourite, in my 1999, is that when a little ground under the front passenger seat is disconnected, the right turn signal flashes the overhead light.

 

I'm in PA. Wow there is alot I have to check. Didn't realize there was that many grounds hidden. Guess when I have a nice weekend I know what I'm doing. Thank you very much.

 

That's just classic!

 

Others on here know much more than I about XJ wiring, so listen to them when the chime in.

However, keep this in mind: a voltage drop such as you're seeing will occur when there is a large current load. It could be an actual load - or it could be a short. Have you checked your headlight switch?

My first inclinations would be a short, a faulty voltage regulator, or bad battery...though you say it's new.

 

Dont think I noticed it in your post, you did upgrade ALL of you wiring to be able to handle the 200Amp alternator. Plus, you got it load tested. Is it actually putting amperage out. Can it handle the demand.

 

Yeah I replaced the headlight switch also. I changed so much stuff it's not funny. Thus explaining the frustration.

 

Just to confirm. What size wire did you run for your new setup

 

Actually I didn't upgrade any wires. It's still all the stock wires from the stock alternator. A new 4 gauge battery wire came with the alternator but I wasn't sure if I should run that directly from the alternator to the battery or if there was another way I should hook it up. But non of the ground wires were upgraded. Should I use bigger wire for the grounds and how would I run that new power cable for the alternator?

 

I am still using all the stock wires on the alternator but with my light bar and auxiliary fan have all new wiring with fuses and the new headlight wiring harness is connected to the stock main wiring harness for the jeep. And also I had to cut of the plug and used those tube krimp wire connectors that the headlight wire harness plugged into the main harness cause the plug was so badly corroded and the wires were actually breaking out. So the connection is all secure now.

 

You need to upgrade your cables. Shoulda been done before the alternator.

www.kelleyswip.com

 

Chris, you need to upgrade your cables.