When your car won’t start, or you just charged your dead battery, you will need to perform a load test.
If you don't have a car battery load tester, you may use your voltage meter to see the voltage change once you add some load. I collected four different values, and derived two values. These six values will help you understand the behavior of car batteries so that you can decide if you should replace a new battery, or revive your old one.
I recommend taking a 10-second video when you have a good battery so that when you do have a problem, you will have a reference point. It is just 10 seconds for you to take a video in case you need it later. To view a video frame by frame use the period "." key. Note that it is not the greater than sign "＞" even though the symbol "＞" is printed on top of the period "." If you have a short cut key for "＞", it will forward 5 seconds instead of a frame, so use the period key.
If you did not have a reference video, you still can view my video where you can find my data from tests of 16 different cars or batteries that give you a rough range of what a new battery looks like, what an old but working battery looks like, or what an old failing battery looks like, and what it looks like if there is some resistance on the terminal (I used jump cables to simulate it). Please leave comments below to provide your data so that we can cover more different cars and batteries, I will consolidate and present data at my website.
0:00 from from previous video more than a year ago
0:20 battery load tester to test battery under load
0:48 To view frame by frame, use the period "." key and comma key ","
1:10 collect 4 values and estimate battery health
1:30 first heard the starter motor's noise
1:50 Vmotor, Vmin, Fall Time, Rise Time, Fall Rate, Rise/Fall Ratio
2:10 5-year old battery successful start vs failed start
2:30 6-year old battery successful start
3:07 6-year old battery failed start
3:40 charge battery for 1 minute, a failure
4:03 old battery date Apr 2014 6-year old CCA 390A
4:29 new battery date Nov 2020 CCA 640A with jump cable
4:55 new battery without jump cable, and also Audi Q7
5:26 new battery+jump cable+ Lexus ES350 success
5:46 new battery+jump cable+ Lexus ES350 fail, and also another success
6:06 dodge caravan and Audi Q5
6:26 analyzing data , collect more data
6:56 recommend taking 10-second video
7:17 no load voltage vs percentage of charge
7:37 Hydrometer
8:30 only a hydrometer can precisely tell if battery is charged fully
8:50 lead plates & sulfation
9:10 view a video frame by frame use the period key not short cut key "＞"
I also have a few other car battery videos that will help you diagnose car battery problems, recondition , re-charge or regular battery maintenance.
3 Car Battery Truths/Myths: Not Fully Charged, Overcharged and Epsom Salt: [ Ссылка ]
Best car battery troubleshooting, correct diagnosis and proper fix with certainty : [ Ссылка ]
