94 LS400 eating batteries
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From: OK
94 LS400 eating batteries
Let me see if anyone else has had this issue. Not really driving the old 94 (around 150k miles) much at all. Have been intending to sell it for a while but the dang thing kept eating batteries. Bought a crap, but cheap 2-year battery from Walmart, yeah, I know, but didn't want to drop a lot on it. Ate about 6 of those things, they'd just crap out after a while, sometimes less than a month into it, hah hah. Resorted to getting an Interstate battery from Costco and low and behold, it has killed this one too.
Battery is less than three months old and it wouldn't charge and I couldn't get it to jump start. Multimeter after charging it only went to 12.2 so I knew it was probably fruitless to try to jumpstart it but tried anyway and NOPE. The alternator is not that old and last time I checked it the reading was fine. But what would kill these batteries, besides the fact Wally World sells junk but the Interstate too?
Battery is less than three months old and it wouldn't charge and I couldn't get it to jump start. Multimeter after charging it only went to 12.2 so I knew it was probably fruitless to try to jumpstart it but tried anyway and NOPE. The alternator is not that old and last time I checked it the reading was fine. But what would kill these batteries, besides the fact Wally World sells junk but the Interstate too?
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From: CA
Define "kill" as we need to know if they're faulty or something else is draining these batteries. If you've tried to start the car & only heard a click then most likely, it's your starter not the battery. Anyway, if it's the batteries (which I doubt very much since you've replaced like 6 of them) then the easiest way to troubleshoot & find out is to turn your multi-meter into an Amp meter & connect it in series w/ the battery. Once you've done that, take note of how much DC current your car is drawing from the battery then start pulling fuses, 1 at a time. Once you've found the 1 that drew the most current then you can zero in which component(s) or circuitry(ies) & go from there. Good luck.
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Check the lights in the glove compartment & the trunk as well. You may think it's off but it may not be due to a faulty switch. The test that I've mentioned above will pinpoint you to a faulty component(s). You could also have an electrical short somewhere in your car i.e. a power wire that the insulator may have been nicked/cracked due to old age & it's running along the metal part of your car & creating a resistive path to ground. There's a different between a resistive short vs a dead short. A resistive short will draw current base upon the resistance path it's creating & eventually drain your battery whereas a dead short will draw as much current as your battery can source & blow your fuse. Based on what you've described, I don't think you have a dead short.
Last edited by Superfast1; Aug 19, 2020 at 02:55 PM.
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Define "kill" as we need to know if they're faulty or something else is draining these batteries. If you've tried to start the car & only heard a click then most likely, it's your starter not the battery. Anyway, if it's the batteries (which I doubt very much since you've replaced like 6 of them) then the easiest way to troubleshoot & find out is to turn your multi-meter into an Amp meter & connect it in series w/ the battery. Once you've done that, take note of how much DC current your car is drawing from the battery then start pulling fuses, 1 at a time. Once you've found the 1 that drew the most current then you can zero in which component(s) or circuitry(ies) & go from there. Good luck.
Thanks for the reply, will try that!
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Joined: Aug 2014
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Check the lights in the glove compartment & the trunk as well. You may think it's off but it may not be due to a faulty switch. The test that I've mentioned above will pinpoint you to a faulty component(s). You could also have an electrical short somewhere in your car i.e. a power wire that the insulator may have been nicked/cracked due to old age & it's running along the metal part of your car & creating a resistive path to ground. There's a different between a resistive short vs a dead short. A resistive short will draw current base upon the resistance path it's creating & eventually drain your battery whereas a dead short will draw as much current as your battery can source & blow your fuse. Based on what you've described, I don't think you have a dead short.
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Joined: Sep 2010
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From: NA
Let me see if anyone else has had this issue. Not really driving the old 94 (around 150k miles) much at all. Have been intending to sell it for a while but the dang thing kept eating batteries. Bought a crap, but cheap 2-year battery from Walmart, yeah, I know, but didn't want to drop a lot on it. Ate about 6 of those things, they'd just crap out after a while, sometimes less than a month into it, hah hah. Resorted to getting an Interstate battery from Costco and low and behold, it has killed this one too.
Battery is less than three months old and it wouldn't charge and I couldn't get it to jump start. Multimeter after charging it only went to 12.2 so I knew it was probably fruitless to try to jumpstart it but tried anyway and NOPE. The alternator is not that old and last time I checked it the reading was fine. But what would kill these batteries, besides the fact Wally World sells junk but the Interstate too?
Battery is less than three months old and it wouldn't charge and I couldn't get it to jump start. Multimeter after charging it only went to 12.2 so I knew it was probably fruitless to try to jumpstart it but tried anyway and NOPE. The alternator is not that old and last time I checked it the reading was fine. But what would kill these batteries, besides the fact Wally World sells junk but the Interstate too?
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From: OK
Instead of using an ammeter and pulling individual fuses, an easier way to check to for current draw is to check for voltage across each of the fuses. The video explains the basics.
https://youtu.be/T6rDTtxaeJ4
https://youtu.be/T6rDTtxaeJ4
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From: SoCal mtns.
Multimeter after charging it only went to 12.2 so I knew it was probably fruitless to try to jumpstart it but tried anyway and NOPE. The alternator is not that old and last time I checked it the reading was fine. But what would kill these batteries, besides the fact Wally World sells junk but the Interstate too?
My LS issue was going flat when sitting.It could be dead in a week,2 weeks it wouldnt start for sure.I believe the correct max draw sitting is 50ma? If Im wrong correct me,anyway I was right at the top allowable.
Anywho wife wasnt about to let me put a solar panel on or near it like I did for my Jeep that can sit for months and is always at 12.8 volts now.
So I bought a battery tender,ran nice wires purchased from ebay to battery to a plug on bumper and its always plugged in and fully charged,and never discharging which is death to batteries.Simply plug and unplug when driven,its no biggy at all to do that.Clean look too.Might not be the 'proper' fix but for less than a hundred bucks its fixed,and will probably pay for itself quickly just in battery longevity.
Last edited by spuds; Aug 30, 2020 at 09:53 PM.
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From: MD
You can try this
Last edited by FloridaCam; Aug 31, 2020 at 02:53 AM.
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From: SWEDEN
Recommend to Use a simple cigarette lighter thing that tells the voltage. Then you can see what is going on easier. If the battery is sound and the alternator does its job it should show >13 V and stay there soon after starting. If the battery is weak it may take a while to go >13 V
It should when igintion us turned on show 12+ V if it has descent charge. If is has degraded to <12V after a few days sitting it is probably discharging due to a problem with ignition off. Could be a sticky sensor leaving a light on or simmilar.
Running a cheap car battery to completely flat will degrade it fast. It normally will survive a handful of times before giving up completely though.
It should when igintion us turned on show 12+ V if it has descent charge. If is has degraded to <12V after a few days sitting it is probably discharging due to a problem with ignition off. Could be a sticky sensor leaving a light on or simmilar.
Running a cheap car battery to completely flat will degrade it fast. It normally will survive a handful of times before giving up completely though.
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