mogulman

I have a 2013 GLK350. Not a lot of options.

​​​​About a year and a half ago, we were on vacation for a week, came home and the battery wasn't strong enough to start the car. I got a new battery at the time. Duralast from Autozone.

Went away for about 3 weeks and left the car in the garage last week. Came home and it wouldn't start. Jumped it and now it seems fine.

Is that normal? Anything that could be draining the battery?

The only aftermarket item I have hooked to the car is a Mid city engineering remote start. It has a cell module attached. Maybe that's draining the battery?

Seems like it shouldn't though.

Mmr1

Sure the mid city module pulls power. Charge the battery and get it tested , since you don’t know how low it got, fully draining it means it will never fully charge again, since you don’t know if it got that low it could have been damaged draining it. It’s still under warranty. Get a battery maintainer for your next trip.

Mmr1

Once I bought a new battery, 6 months later it failed and left me stranded, I was given a new one free. Defects do occur.

mogulman

Got a battery maintainer. Charged it up. Will get it tested tomorrow.

mogulman

Went to AutoZone. Battery registered ok ,but only had 26% charge after being on battery tender 4.5amp overnight. Manager replaced battery for me as battery was 2 years old but has 3 year warranty.

Mmr1

I was thinking of a cheap replacement for my 7 yr old Varta AGM battery , now I wonder . Consider getting a real battery tester, Solar makes one that’s cheap and quick to use it measures CCA . 2 years on an AGM battery is a joke , mb batteries last 7-8 years My 2013 still reads 75% at 12.5v after sitting overnight .

Mmr1

Look at a Solar BA7

mogulman

BA9 is cheaper. Same functionality.

I'm going to wait and use my local auto parts store though.

I did replace my aux battery from 2012 though, in case that was drain my main.

dave2001auto

usually Pepboys has a Black Friday and Cyber Monday sale. $30 to $40 rebate and discounted price. I think with all the sale it was $120 to $150 for the AGM battery with 4 year free replacement.
check for parasitic drain and locate the source by pulling on fuse at a time.
My good battery at 80% when dead in a month.

Mmr1

I didn’t know about the ba7, it probably came out after the ba9