Hi All,
I'd like to replace the main battery on my 2019 GLA 45 AMG (perhaps going with Optima Yellow Top H6). I have a few questions:
1) I would like to replace the battery without having to reset any system memory. Therefore, I'm thinking of just connecting a secondary 12 V battery that I have lying around in parallel to the installed battery so that when I remove the installed battery, the system does not ever lose power. To this end, I'd like to know if I can connect the secondary battery to the locations shown in the below image (ignore the yellow leads of the battery charger that's currently hooked up). The white lines trace what appear to be the paths of cables that connect the battery terminal clamps to locations in question. A voltmemeter shows that the voltage across the two circled locations is the same as that of the battery, and going from positive of the battery to the circled negative also gives the same reading, as does going from the negative of the battery to the circled positive--all as would be expected.
![Image]()
2) I remember reading somewhere about resetting the alternator so that it adjusts itself to the new battery. How is this reset done? In some forums, for other Benz models at least, I see mention of resetting a BMS, which I assume stands for "battery management system".
3) In terms of keeping the system memory, would it be better to just buy and learn to use a so-called memory saver (I honestly know nothing about them; I just noticed that such a device exists)?
4) Any other considerations to take note of when replacing the main battery?
Thank you,
Andy
FWIW, the service manual instructions for battery replacement are attached below. They don't seem to address the reset of the alternator, electrical system reset, etc.
I'd like to replace the main battery on my 2019 GLA 45 AMG (perhaps going with Optima Yellow Top H6). I have a few questions:
1) I would like to replace the battery without having to reset any system memory. Therefore, I'm thinking of just connecting a secondary 12 V battery that I have lying around in parallel to the installed battery so that when I remove the installed battery, the system does not ever lose power. To this end, I'd like to know if I can connect the secondary battery to the locations shown in the below image (ignore the yellow leads of the battery charger that's currently hooked up). The white lines trace what appear to be the paths of cables that connect the battery terminal clamps to locations in question. A voltmemeter shows that the voltage across the two circled locations is the same as that of the battery, and going from positive of the battery to the circled negative also gives the same reading, as does going from the negative of the battery to the circled positive--all as would be expected.
2) I remember reading somewhere about resetting the alternator so that it adjusts itself to the new battery. How is this reset done? In some forums, for other Benz models at least, I see mention of resetting a BMS, which I assume stands for "battery management system".
3) In terms of keeping the system memory, would it be better to just buy and learn to use a so-called memory saver (I honestly know nothing about them; I just noticed that such a device exists)?
4) Any other considerations to take note of when replacing the main battery?
Thank you,
Andy
FWIW, the service manual instructions for battery replacement are attached below. They don't seem to address the reset of the alternator, electrical system reset, etc.
