MG CAR OWNERS FORUM

Salutations everyone,

Shortly after I got a new Bosch battery for my 2014 E250 diesel, I changed the battery out. Just about two weeks ago, the battery was at 10.9 volts, but the car still wouldn't start. It worked fine after I got it going, but today it wouldn't jump start at 9.5 volts. All is well again after the battery was swapped. It seems like there must be a drain somewhere, or I've read that the car should be informed about the new battery through software, since otherwise it will keep charging at the old battery's rate, which could cause damage. Does anyone have any idea if this is true?
Much obliged.

I believe the issue may be with something else, because I have successfully swapped out the batteries in two 2016 and 2017 Mercedes vehicles without informing the software.
Is the car used for short trips or does it sit for long periods?

Can you tell me the tick over and load readings of the alternator?

Were AGM and lead acid substitutes considered?

Did you change out a Bosch battery that was 10 months old? Was the work done as part of a warranty, if so?

I swapped out the Bosch S5 A11 agm for 14.7 while the vehicle was running.

Sure, I bought it at Costco.

I was made aware of a battery issue about a month ago when an MB specialist advised that the battery was showing two codes on their diagnostic system; over the weekend, a red battery warning message stating, "STOP THE VEHICLE, SELECT P DO NOT SWITCH OFF ENGINE" appeared on the dashboard.

1, B1F4500: Restarter Battery Has Too Much Resistance 2, B21059A: Starter Battery Capacity Is Inadequate, Compenent Operating Conditions Are Not Satisfactory, Or System Requirements Are Not Fulfilled

"Current!" and "Stored!" appear in both messages.

Since my breakdown coverage with the RAC includes battery replacement, I have contacted them.the time has come to sit tight. It is not too bad since I am at home. I believe it's reasonable to say the battery is cattled because I've had the car since 2019 with the same battery when I bought it. The car is a C220 w205 on a 2015 plate.