Battery not holding charge, dead?

theRealCrazy

JK Enthusiast
Joined
Feb 12, 2020
Messages
133
Location
Los Angeles
Yesterday morning car barely started , checked the voltage and it was under 10.0v oO... engine starting goes back up to 13.7v...
I thought, because I changed the HU that I might have a faulty ground somewhere, so I decided to remove and unplug the whole HU... I charged the battery again and this morning back to 9.7V... I then decided to unplug the battery fully. I started charging it.. up to 12v, then using my voltmeter on both terminal I literally can see the voltage drop.... almost. 0.1v/2sec... oO

I plugged a Pulse repair that I had laying around... but wanted to get your opinions..
 
When your Eng is running and your Alt is good, 14.3 to 14.7 Volts PE across the battery terminals with a calibrated DMM is normal. After a charge and no load the lead acid will drop to 12.3 (give or take). Simple tests first, load test your battery. A shop or in my case a Foxwell BT -705. Questions? What is the acronym HU ( Head up Display?) And a Pulse repair?
 
? What is the acronym HU ( Head up Display?) And a Pulse repair?
Hu is the headunit (radio/nav) pulse repair is a way to charge difficult batteries, can take 24/48h but I usually had good results with my TJ's battery.
Well, I'm going to wait patiently till it shows full and check with the voltmeter again just on the battery disconnected to see if I lose voltage.
 
Ok so I did a small video looking at the voltmeter. The battery is totally unhooked from everything...

Does that mean the battery is dead, or is there is a way to fix that?

Video link

For people who don't want / can't watch the video.. it's a 1min video where voltage drops from 11.44 to 11.39 in a minute
 
The fact that the battery voltage is less then 12v usually means time for a new battery, most are usually always in the 12.2 to 12.5 range when just sitting.
 
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yeah doesn't want to go over 11.5V using the charger... i went ahead and ordered an Optima yellow top H6 one... hopefully that'll last.
 
Alright, battery was indeed the issue.
12.35v steady 😍

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