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tkoTJ 04-02-2008 01:41 AM

Wrangler Battery Drained and Will Not Jump
Hi everyone,

I've got a problem and I'm hoping some Jeep fanatics out there have seen or possibly know whats wrong.

So this past weekend, I realized my fog lights were turning on by themselves via the multifunction switch (also controls signals, headlights, and highbeams), something was loose because I'd have to press and hold the switch to keep the fog lights from turning on (even when the car was off). Well, needless to say, my battery has drained overnight.

Well today, my brother came over and tried to give me a jump start, but our efforts have failed. I disconnected the bulbs from the fog lights to prevent them from draining the power from the jump, but that didnt work. I also took out the fog light indicator (which was permanently on in the dashboard when hooked up to my brothers car) in case that was draining the power from the jump, still no luck.

My brother's guess is the alternator or starter needs to be replaced. My question is if my battery drains, could that potentially affect my alternator or starter?

Any help would be greatly appreciated.

This is a 01 Sahara with about 60K.

Thanks in advance.

AzTJ 04-02-2008 02:00 AM

Hmm... I doubt the alternator or starter has anything to do with it. If the fog light switch is busted and stays on, that should be replaced.

Does the door ding or lights come on when you hook up the battery to get jumped?

Smeghead 04-02-2008 02:03 AM

for grins connect the negative terminal to the body somewhere, that worked for me one time when my battery was just shot

tkoTJ 04-02-2008 02:58 AM

azTJ - yes the lights work when connected to a battery. headlights, turn signal, everything, even the radio.

if i disconnect, i'll have power for a minute or so and it'll fade out.

tkoTJ 04-02-2008 02:59 AM


i think your right in replacing the multifunction switch...what i dont get is why i wouldnt be able to jump the car with that switch broken?

parrot head 04-02-2008 09:09 AM

:zap:With a completely dead battery you need to leave the jumpers hooked up for a while to the "live vehicle" with it running in order to get some charge into the dead battery. Right now the dead battery is sucking up all the amperage. If you do this for about 10 minutes or so, it should work. However the best method is to charge the dead battery with a charger. If your dead battery is a couple years old, just replace it. When you kill a car batt that bad, you shorten its life anyway.:zap:

MoA 04-02-2008 09:28 AM

like parrot said a completely drained battery will take forever.. took my buddies rubi 20 minutes to charge..

my jeep started doing the same thing and it was a bad battery.. had a lifetime warranty on it through sams club and got a brand new one.. and it went bad too.. it could also be the battery terminals.. my jeep's need to be replaced, they are corroded and ive had problems with my battery keeping a charge because of it

rebelBullDawg325 04-02-2008 09:55 AM

if its dead it'll take a while... also, are you hookin +to+ and -to- or are you going -to(grnd)? if its a stick shift, you could pop the clutch to start it and drive it aroudn for a little while, this should charge the battery

Jerry Bransford 04-02-2008 10:49 AM

When a battery is totally dead, the alternator will be dead too. The alternator needs at least some voltage from the battery (called an exciter voltage) to work so if the battery's dead, the engine won't run once you remove the jump battery.

And you can't push start a Jeep with a dead battery either, for the above reason. Note I said 'dead'... because a battery that is simply too low to start the engine but not completely dead will allow a Jeep with an alternator to be push started and the engine will run.

Some alternators like, I believe, in GM vehicles don't require the battery to work but Jeep TJ alternators do.

rebelBullDawg325 04-02-2008 12:20 PM

well i stand corrected. thanks for that info jerry

tkoTJ 04-02-2008 03:28 PM

thanks everyone for your input...i'm going to buy a new battery and try that tonight after work.

i'll update this post to let you know if that solves the problem. THanks!

tkoTJ 04-02-2008 06:20 PM

hey gang,

can someone walk me thru the steps of replacing a bad multifunction switch. before i fix the battery i'm guessing i should replace this switch or it'll drain my new battery.

is this something that is simple to do by myself? or is it better to leave this to a professional. thanks in advance again.

Triple88a 04-02-2008 06:38 PM

last month my battery also died. I dont think i left anything running but anyhow.. i had my moms FJ hooked up for half an hr.. still couldnt start.

tkoTJ 04-02-2008 06:48 PM

hey triple88A,

did you end up replacing the battery? did you ever find out what caused the battery to die?

fyi, this is the original battery when i first bought the car back in its time to get a new one.

Triple88a 04-02-2008 07:01 PM

i think the battery was just old, either way it would not jump even when chargnign it for about half an hr and the FJ revving at 4k. With the new battery i havent had any problems yet. Once i had my jeep barely start because the engine light somehow got stuck turned on even with the hood closed.

tkoTJ 04-02-2008 07:17 PM

awesome...from all the input here it looks like its just my battery...which is a relief...

now for the multifunction switch swap out...anyone out there thats done this themselves?

[TheYJGuy] 04-02-2008 08:02 PM

My starter was shot on my YJ for the last 3 months that she ran, so I just pop-started it every time.

1. With your foot on the clutch, have someone push it or let it roll a bit if you're parked on a hill.

2. Shift into 2nd gear.

3. Dump the clutch.

Works every time :punk:

tkoTJ 04-04-2008 02:31 PM

thanks to everyone in the forum!

battery swapped. no problems...mulitfunction switch swap out is super simple as well.

Jerry Bransford 04-04-2008 02:37 PM


Originally Posted by The_YJGuy88 (Post 214527)
My starter was shot on my YJ for the last 3 months that she ran, so I just pop-started it every time.

1. With your foot on the clutch, have someone push it or let it roll a bit if you're parked on a hill.

2. Shift into 2nd gear.

3. Dump the clutch.

Works every time :punk:

Not if it's a dead battery as the OP had. Check out post #9 above if you missed it. :)

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