Electrical issue... grounding? short?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Fless

Staff member
Super Moderator
Joined
Apr 2, 2017
Posts
10,467
Reaction score
20,793
Location
Elev 5,280
Humor us and get the battery charged and tested, just to rule it out. Go from there.

You could put a current meter on it (DVOMs can usually handle 5 or 10 amps through the current ports). Might blow the internal fuse if it's more than it can handle, but then you'd know.
 

JamesLond

Full Access Member
Joined
Feb 2, 2022
Posts
123
Reaction score
82
If you don't have a battery tester like this one, I'd second taking it in to the parts store and having it charged. Their charger both tests and charges the battery.

They'll definitely let you know if it's bad.
 
OP
OP
N

nosole

Member
Joined
Jun 14, 2016
Posts
50
Reaction score
13
So, as of now, I can confirm it is a bad battery. I charged it yesterday, let it sit overnight, and it discharged to about 12.35V. Took it to autozone just now to get tested and it is indeed bad.

I do feel like there’s another gremlin lurking, but I’ll have to wait to see until I get a new battery in there.

Thanks for all your help so far.
 

rockola1971

Full Access Member
Joined
Dec 29, 2016
Posts
2,386
Reaction score
2,999
Location
Indiana (formerly IL)
So, as of now, I can confirm it is a bad battery. I charged it yesterday, let it sit overnight, and it discharged to about 12.35V. Took it to autozone just now to get tested and it is indeed bad.

I do feel like there’s another gremlin lurking, but I’ll have to wait to see until I get a new battery in there.

Thanks for all your help so far.
A bad ground causing the BCM not to goto sleep will ruin a battery and give similar symptoms that you are experiencing. A car battery is not designed to be loaded down towards zero volts and cycled from low charge to fully charged alot. That is what a deep cycle is designed for. Deep cycling a car battery will ruin it and that is what happens when chasing the famous BCM wont goto sleep scenario.
 
OP
OP
N

nosole

Member
Joined
Jun 14, 2016
Posts
50
Reaction score
13
A bad ground causing the BCM not to goto sleep will ruin a battery and give similar symptoms that you are experiencing. A car battery is not designed to be loaded down towards zero volts and cycled from low charge to fully charged alot. That is what a deep cycle is designed for. Deep cycling a car battery will ruin it and that is what happens when chasing the famous BCM wont goto sleep scenario.
Thanks! I'll keep an eye on that in case anything flares up.

Got a new battery, popped it in, and all the weird issues vanished. I feel silly for trying to read too far into this, but I've never had a bad battery create such logic defying (at least for me) symptoms. But hey, this all goes in the experience vault for next time, so I'll take it as a valuable lesson.

Thanks all for your input! Very much appreciated!
 

rockola1971

Full Access Member
Joined
Dec 29, 2016
Posts
2,386
Reaction score
2,999
Location
Indiana (formerly IL)
Thanks! I'll keep an eye on that in case anything flares up.

Got a new battery, popped it in, and all the weird issues vanished. I feel silly for trying to read too far into this, but I've never had a bad battery create such logic defying (at least for me) symptoms. But hey, this all goes in the experience vault for next time, so I'll take it as a valuable lesson.

Thanks all for your input! Very much appreciated!
To give you more insight on exactly what happened we have to dig into what is a battery. Your "automotive battery" isnt really a battery. It is a Jar or Cannister with multiple batteries (cells) inside. They are situated in series. So if one goes dead or electrically opens up the whole string is useless (just like cutting a wire in half). If one of those batteries (cells) becomes weak then it drags down all the cells because they are in series. The max amount of current that can flow through a series circuit of batteries is limited to the amount of the weakest cell since that weak cell cant flow current as high as the others. So your battery had a bad Cell or even more than one. The amount of voltage and current flow was limited and not up to spec. The Instrument Cluster has electronics that only work within a specific voltage range. If the range is not met then it goes crazy and does all sorts of odd things.
Moral of the story is if electronics are going crazy then the first thing that should be done is LOAD TEST the battery. Notice I did NOT say test the battery. Test could mean alot of things to different people. A load test checks the voltage output and current providing capability of a Battery. Just checking the voltage of a battery with a voltmeter gives you a very limited amount of information to start with but it can yield a clue. For instance if you go out and measure with a voltmeter and the battery is 10.9v then its either a bad battery, been discharged by something or the alternator isnt charging it........ Or you are getting a bad reading because your battery terminals are corroded. See how all those went different directions for troubleshooting.
 

Forum statistics

Threads
129,220
Posts
1,812,319
Members
92,320
Latest member
RanchoTexas
Top