Driving With Dead (Shorted ) Battery

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Dec 2, 2020
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I just had my first experience with a battery failure with no warning. The battery was completely dead (shorted) with voltage under 2. It was an OEM battery that was 18 months old, with 4500 miles. I charged it once every week and the vehicle was garage kept. Lucky for me, the battery failed in my garage. Obviously these type of failures could occur anywhere. I am thinking of buying a portable jump starter so I can start my car and get it to a shop or to my home if this occurs away from home.

Question 1 Will it damage the alternator or electrical system if I jump start and drive my car with a shorted battery for 30 minutes to an hour to get it home?
Question 2. Could anyone recommend a good portable jump starter?

Thank you.
 
Are you sure of the failure type? Chargers can fail and kill batteries too.

1. Yes, it could and it depends on what the alternator sees for voltage and resistance. Weakened low voltage batteries, that willingly take a charge, can overheat an alternator. So, you'll have to be sure of the battery failure by using an ammeter with engine running to see if you're stressing the alternator. If there is super high charge current... frying time. If the battery voltage jumps to ~14v with minimally current, other than normal vehicle draw, then no expected alternator damage. But, some cars 'manage' charging and could cause your vehicle to stall when running off battery with alternator in an "MPG" improving state. So, it'll depend on year/make/model/vehicle and its ecu-controlled alternator/battery usage/charging algorithm.

2. I like and use the NOCO products.

If you knowingly have a dead battery and good alternator, best bet is to hitch a ride to buy a replacement and not drive around.

Is your battery under warranty? If so, exercise the battery/store warranty. If vehicle is under auto manufacturer warranty, might have to tow to dealer to exercise auto manufacturers warranty... as some dealers won't recognize a dead battery unless its still in the vehicle.
 
Question 1 Will it damage the alternator or electrical system if I jump start and drive my car with a shorted battery for 30 minutes to an hour to get it home?
Question 2. Could anyone recommend a good portable jump starter?
1) Shouldn't. If it does, the alternator was already on it's way out.
2) Plenty of online reviews and tests to research.
 
prolly NOT as i believe todays car battery is the reserve + everything runs off alternator output + with sooo many gizmos you MIGHT really end up with costly repairs! as noted try a good battery to see otherwise a rollback to your favorite shop, good luck!
 
It's not a great idea.

I drove a car with one shorted cell, it read 10.3 volts when off. So each of the 5 remaining cells saw ~2.9 volts, which is the equivalent of a good battery seeing 17.5, which is significantly overcharging.

Needless to say there was acid everywhere under the hood, under the battery tray, inside the subframe rusting it out, etc.

Does your warranty include roadside assistance? Get it towed in for a new battery.
 
Nowadays no since everything's better protected electronics wise. Some older cars would just keep trying to charge a shorted battery since they weren't able to detect the resistance and would overheat by overloading and would just roast whatever was left of the dead battery and cause acid to go everywhere. But it's fine if you run it like that for a bit. To be on the safe side once it's started you can just leave a post disconnected and isolate it with like a rag knotted around it so nothing can't happen. It'll supply power to itself but not to the battery if it sees an issue in trying to charge it or if there's no voltage to read and thus nothing to receive charge. As for portable packs i don't know but i'd just get the battery replaced. I once had dura last gold last me 3 years and 2 months so it was out of the warranty which pissed me off. The value craft i bought right after that duradud lasted me 5.5ish years if you can believe it. Don't know about the econocraft AutoZone offers.
 
I once drove to the auto parts store in the lemon 99 Taurus, with a jumper battery pack doing the job of the battery, which was still there in some heavily discharged state. We were miles from home, but only minutes from an auto parts store.

The Taurus would die the moment the jumper battery pack was removed.

Years later the battery cable eroded completely off of the positive terminal on our 05 Pilot. The vehicle kept running like that, wife drove it home in that condition.

Mystified, I looked it up. The Pilot had a self-energizing alternator. The Taurus did not. So that difference may influence the possible success of your venture.
 
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When the battery in our van failed it shorted a cell and wouldn’t run without the jump pack connected or above 2000RPM with it disconnected but that causes anything electrical to freak out, flashing lights, gauges jumping around erratically, wouldn’t idle, etc.

Edit - seeing Hangfire’s post I guess our van also doesn’t have a self exciting alternator, would have never thought that!
 
Question 1 Will it damage the alternator or electrical system if I jump start and drive my car with a shorted battery for 30 minutes to an hour to get it home?

Years ago, I had a Ford Contour. The battery didn't have enough power to turn the engine over, so I had my brother push it and I popped the clutch and got the engine started. I dropped him off at work and got on the interstate to see if I could charge the battery up by driving.

While I was on the interstate, it started to rain so I turned on the headlights.

As I did so, the engine misfired. Yes, it misfired at 70MPH. It felt like it lost power for a split second.

Best that I can guess is that the action of turning the headlights on, in conjunction with a bad battery, caused the system voltage to drop so low that the ECU crashed, causing the misfire.

My next stop was to Montgomery Ward to buy a new battery, whereupon they didn't have a battery that fit but crammed a 58R into it.

I noticed, after I got off the highway, that it didn't want to idle. There was clearly something wrong with it, I had to give it a bit of gas to hold the idle up.

All resolved with a new battery.

My suggestion...do NOT drive with a bad battery.
 
Thanks for all your replies. You have given me a lot to think about. I appreciate your time and experiences.
 
I have been caught twice with zero volt battery. Smart charger do not charge from If your battery has dead cells, then you will not get 12+V even when fully charged.
I would look at the price of a non smart old fashion charger instead of jump start pack.
You could connect another battery pack (another car or power pack) but let your battery take in some charge first and then check the volts on it.
 
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