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Parasitic drains and ground locations...

1K views 14 replies 5 participants last post by  mayeni 
#1 ·
Hey guys, so like many, Im having a pretty bad parasitic drain issue with my 96 XJ. Seems as the problem has gotten much worse since Ive installed my new head unit. Brand new battery (which I plan to swap out for a new optima soon) and brand new alternator, both good. I made sure the radio ground to the original radio ground was a good connection but Im going to add an extra ground right behind the radio to hope that helps. Beyond that, Im a little lost. I know this problem isnt new to this jeep because I can tell the PO unplugged the underhood light, glove box light and pulled all the interior overhead bulbs already, but even still, the battery is barely surviving a day, sometimes not even... definitely could appreciate some help from others who may have had or have this problem. I was hoping to someone could provide me a location for all the ground locations for a 96 XJ so I can start working on cleaning and or replacing them all, like the one at the negative cable, one at the back of block, etc, etc. Any help would be MUCH appreciated here guys, this is one of the last few quirks Im trying to iron out with this Jeep before i call it almost perfect. Thanks!
 
#2 ·
Have you put a DVOM on the battery, & then One by One start pulling fuses. After you pull each fuse, wait about a minute to see what the DVOM is doing, & then upon replacing each fuse, wait another minute to see what the DVOM is doing. This should lead you in the correct direction to see what circuit is causing the drain.
 
#5 ·
Sorry about that.
- DVOM = Digital Volt Ohm Meter.

Mr. Jay-h is spot on. I ask you to wait a minute in pulling fuses, just so the car can go through it's cycles as you pull fuses. Keep in mind if you have a dome light that stays on for 20-30 seconds that will show a draw & you need to wait for the car to go through it's cycles. Make sure doors are all closed. Radio is off, key is off & in your pocket, so you know where it's at. A helper could make things easier as you pull fuses. If you want to do a test run, have everything hooked up, door closed & wait 30 seconds so the car can cycle with its courtesy lamps & what not. Now, ask your helper to turn on the parking lights, or even step on the brakes. You'll see the draw go up. Turn off the parking lights or release the brake pedal & you'll see the DVOM return to what it was when you started.

Check out the video, & maybe watch afew more videos to get an idea as to what is happening.

 
#4 ·
Digital volt meter.

What you actually need to do is measure current draw, so you will need to disconnect one of the battery cables (with everything turned off) and put the ammeter in that circuit. Start with at least 10A range, go down as appropriated.

30-50 mA is ok.You're looking for something larger like half Amp or more. As noted above, start pulling fuses until it drops.
 
#6 ·
Hey guys, thanks for all the info. I brought the jeep to my job today and borrowed a buddys meter and test light. I read in another forum to disconnect the negative terminal and connect the test light to the batt and cable and see how bright light is; mine was bright. I then did the same with the meter. Im not sure how use it but I set it to mA which I assumed was milliamps, and with it connected it read .67-.69. I then proceeded to pull EVERY fuse, from both the underhood and under dash fuse box, and check the meter each time; no change for any fuses at all. Now Im just kinda lost. Im not an electrician by any means so this is a harder one for me. I decided to clean the battery ground to the fender, I replaced ALL the battery cable ends at the battery, replaced the battery under warranty, made sure all my connections were clean and coated them all in a light film of dielectric, and then since things seemed to be worse since I installed my new aftermarket radio, I pulled that yet again, and added another ground to the original ground going to the Jeeps harness, and grounded it to a piece of body metal behind the gauge cluster. I ran out of time there, and Im gonna monitor things now, but I dont think any of that is going to fix the issue. I also have both the glovebox and rear hatch light unplugged for now also. Does anyone else have any other suggestions or ideas? Also, any other grounds throughout the vehicle worth checking? I appreciate all the info.
 
#7 ·
First, grounding can cause some problems, but not battery draining. So don't be worrying about ground at this point.

Secondly 67 to 69 mA will NOT drain the battery.

Two possibilities

1. This is an intermittant problem, only under certain circumstances.

2. It's not a drain problem at all. Try disconnecting the battery tonight, connect it tomorrow and see what happens.




Also: when you say barely survives a night exactly what is happening? Do the headlights work? When you try to start, does it click? What are the symptoms.

One possibility is a bad cable, but a little information about above will help.
 
#8 ·
Jay-h, thanks for all this troubleshooting help so far. By not surviving a night, I mean I?d come home from work, park it for the night, go to leave for work the very next day at 7am, and it would be stone dead; no lights, no cranking not even clicking, dead as if there wasn?t even a battery in it. Thats just been most recently, a week or so a go it was getting weaker but still had just enough to crank until it started, so it?s like something has been wearing it down worse and worse over time.

One thing that just came to mind that Ive also been having a problem with is my power door locks and I now have to wonder if its related. Just recently, my power door locks stopped working, which I feel like started after a car wash. All of my power windows work fine from their switches, but neither power lock or unlock switch works. On either, if you press the switch to unlock, a clicking sound can be heard from the relays under the dash, press the switch to lock, and nothing, not even the clicking sound. Ive tried replacing the lock and unlock relays but that did nothing, so my next step is going to be to take off the door panels, pull the switches and clean all the contacts and apply some dielectric grease, and grease all the lock mechanisms in the doors (because its also extremely hard to move the manual lock button for the doors too, so I assume everything is dry and stiff inside). But I wonder if somehow this is all related because when the battery dies, and I jump it, or like when I put the new battery in yesterday, I heard a light thump instantly, and went to the doors, and all the doors had locked automatically (except the drivers door oddly) which I dont think is normal when you are just hooking a battery up.

Any ideas to this at all? I REALLY hope Im not gonna have to try to pull the wiring harness in the doors to check for broken wires or voltage because thats not really my strong suit... Thanks for all the help again!
 
#9 ·
...
One thing that just came to mind that Ive also been having a problem with is my power door locks and I now have to wonder if its related. Just recently, my power door locks stopped working, which I feel like started after a car wash. All of my power windows work fine from their switches, but neither power lock or unlock switch works. On either, if you press the switch to unlock, a clicking sound can be heard from the relays under the dash, press the switch to lock, and nothing, not even the clicking sound. Ive tried replacing the lock and unlock relays but that did nothing, so my next step is going to be to take off the door panels, pull the switches and clean all the contacts and apply some dielectric grease, and grease all the lock mechanisms in the doors (because its also extremely hard to move the manual lock button for the doors too, so I assume everything is dry and stiff inside). But I wonder if somehow this is all related because when the battery dies, and I jump it, or like when I put the new battery in yesterday, I heard a light thump instantly, and went to the doors, and all the doors had locked automatically (except the drivers door oddly) which I dont think is normal when you are just hooking a battery up.

Any ideas to this at all? I REALLY hope Im not gonna have to try to pull the wiring harness in the doors to check for broken wires or voltage because thats not really my strong suit... Thanks for all the help again!
Interesting that you say that. I had a Subaru that would periodically kill the battery and eventually it turned out to be the power door locks.

Try the ammeter again (set to the highest range, maybe 10A) and cycle the door locks. There will be a heavy spike when they flip then should drop way down. Do it a number of times because it might be intermittent of a problem.

You might want to unplug each of the locks... the problem may be a bum lock, not the harness.
 
#10 ·
Automotive batteries don't like being significantly discharged repeatedly and will indeed become less tolerable of it over time.
While you have that meter handy it might be interesting to take a battery voltage reading when you park it for the night and again in the morning. The next night do the same thing but disconnect the cables from the battery first. Take your readings directly from the terminals and not the clamps.
 
#11 ·
Thanks Jay and Chris again for the help! So far, the battery has been okay starting since I put it in Saturday, despite the cold, it?s started for me both Sunday morning and today, but the battery is still brand new so Im still doubtful. Wednesday after work, im pulling the door panels to get in there and clean, lube and grease everything up, including the electrical connectors at the door switches. I may just try calling the dealer and seeing if I can just get new switches for both sides, because I have a feeling its a bad switch also. Jay, I will also check the voltage with the switches and report back my findings. That said, should I WANT to see voltage spikes when I hit the switches or no?

And Chris, thanks, I figured the other battery was probably just beat at this point, as it was charged by the system, and then decharged literally to zero juice; no lights, no click, just dead. I?m ordering a new optima blue top now as we speak. That said, do any of you guys know the best sized optima to fit our battery trays?

Thanks again guys!
 
#12 ·
"That said, should I WANT to see voltage spikes when I hit the switches or no? "

You would see CURRENT spikes at the battery connection (with the ammeter in line). Voltage won't change much.
 
#13 ·
Okay guys, sorry for the long delay in this issue, but things have been crazy with the holidays, work, etc. In the meantime I wound up buying a cheaper Harbor Freight battery maintainer with a quick disconnect that I hard wired to the jeep with the plug hidden in the grille, and just plugged it in every night; the first “plug-in” XJ!

Anyways, I’m still having this issue and finally have gotten back around to tackling it. So I went out and bought myself a good, quality meter and did some quick testing tonight. Following a good YouTube guide, with my battery fully charged and ALL vehicle electronics off (doors closed, hood light unplugged, key off, etc) I disconnected my negative cable and ran my meter in series with the cable and post, and set my meter to how they had it in the video, on the highest amp rating (200A, I believe). The numbers on the meter finally settled down to 1.00a, which I assume to be a 1 amp draw, and from my understanding, REALLY high. I began pulling fuses in the underhood fuse box, and in my ‘96, there are 4 mini-fuses, between the relays and the maxi-fuses, and one of them is a 20a mini; I pulled it and my meter dropped immediately to zero. Unfortunately, I don’t have my original owners manual and can’t seem to locate the fuse layout descriptions for our under hood box, so I started the jeep and found my radio, interior lights, and power door locks don’t work with that fuse removed (granted the door locks haven’t been working either, but the “click” I could hear from the relay on unlock stopped). So now I know my draw is something in that group. I ran out of time, but I guess my next step now is to put that 20a mini back in, and put my meter on the windshield and start pulling the under dash fuses for each of those functions. I think each has its own fuse, one for radio, one for locks, etc, so hopefully I can narrow this down further. I have a bad feeling it’s going to be the power door locks, which is gonna mean me having to pull back all the door boots, dig through the wires.... ugh. I don’t know why I love this Jeep so much sometimes.
 
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