Hi all

Can anyone tell me the way to figure out the age of a battery from the sticker? In addition what size/ type of battery should I have?
I am trying to figure the cause of an flat battery/alternator issue.

Thanks.

 

I don't know of a way to reckon a battery's age from markings on it that will work in all cases.

But whatever its age, a very good test of a battery's health -- better than most "load tests" available at auto-parts stores -- is as follows:
Disconnect the battery from all loads, charge it fully, disconnect from the charger and let it rest overnight. Then measure the battery's no-load voltage with a digital meter. In round numbers you'd like to see something over 12.5 volts.

The battery type that's correct for our cars is "group 49"

 

On the top of the negative post should be stamped a 4 figure number that will give you the week and year of the battery.

As for the cause of a flat battery you need to give us a little more information on condition of the car, how often you drive and whether anything has been done recently.

 

There is not any markings on the terminals. The car was probably sitting around for months before I bought it. It went to the shop for the safety/emissions tests on Wednesday and I took it for my first drive on Saturday, I was out for 40 minutes 1/2 highway half stop start, I had the ac on as well, when I stopped at the house It was dead. Maybe it just needed charging which was done overnight.

 

Hi
The voltage readings were, after charging overnight 13.5, engine running 13.7, ac & headlights on 13.9 engine off 13.4. Six hours later 13.1. How does tha look?
Thanks.
Plastic Paddy.

 

Paddy,

Not many batteries have markings on the neg. terminal. I think this was a BMW practice.

A little confusion here though. We want the voltage produced by the battery itself after charging and an overnight rest ... disconnected from any sort of charging device or the car's alternator. A number like 12.7V is excellent; you won't see anything like 13V or higher.

 

Dennis
Thanks for the input, I disconnected the charger around ten hours ago, I will check again in the morning.

 

I have checked the voltage it is showing 13.1 this is around 22 hours since I disconnected the charger. From the AC Delco website the date on the battery is Febuary 2016.It is looking good.
Thanks.

 

I think jimbov8 was referring to the original Jaguar branded battery fitted to the car when new. Those were made by Varta/Bosch and did have the code stamped there.

 

Are you using a digital meter? Far as I know, 12.8x volts is about as high as lead-acid batteries can go (including AGM batteries).

But I don't want to confuse your investigation. You mentioned a flat battery problem. Generally, three suspects: the battery itself won't hold a charge ... the charging system is not doing its job ... there is some parasitic load that is pulling the battery down even with the car shut off. From what you describe, sounds like the battery itself is not likely to be the problem.

 

usually a battery jsut has a sticker on it. month and year = 12/16 or 0116.
Not many know there are similar codes on tires (in the USA anyway) on the side wall you can see a imprint of the week and year. Say 2516 which would be week 25 of 2016. Usually the numbers are in oval stamped on the tire.

 

The date on the battery is February 2016. I finally got to the bottom of the key issue, thus enabling access to the battery in the back in case it was 'dead'. ( with help from the forum). This afternoon the voltage before it was started was 13.1. I went out for 40 minutes, made a stop turned off engine had radio on, re started no issues, 15 minute drive, turned off engine radio on, went to start, no go, again lights on voltage & oil gauge flashing furiously.
Open the back hooked up a booster, no go, tried a few times, switching booster of as I re positioned the booster clamps, still no go. Pulled the battery cables around, lights stopped flashing, car started without the help of the booster.
Drove 15 minutes back to the house, turned off the engine, lights started flashing again, g to a spanner to the battery terminals and found both needed tightening.
Likely the problem from the start?
I will try it out again tomorrow.
Thanks for all your inputs.

 

The crimp connection on the Positive Battery Cable is a common issue causing intermittent contact, electrical chaos, and no start/start scenarios, most clamp it in a vise, some with vise grips to tighten it back up. The Lugs on the High Voltage Fuse Block behind the spare tire are another area known to loosen up as well causing the same symptoms, and some have had issues with the Ground Cable on the battery.