Anyone changed out the car battery?
Thread Starter
Senior Member
Joined: Jul 2017
Posts: 355
Likes: 44
MY17 C63s Sedan
Anyone changed out the car battery?
I am shopping around for a new battery and wanted to seeing if anyone has already done this and what brand/model did you pick. I am having difficult time finding ones that fit. The two that I found so far is Duralast Platinum AGM and Odyessy AGM. But would like to have more choices if possible.
Thread Starter
Senior Member
Joined: Jul 2017
Posts: 355
Likes: 44
MY17 C63s Sedan
Member
Joined: May 2017
Posts: 90
Likes: 17
Porsche 911, C63S AMG, 300CE 24
When you install a new battery without reseting the battery in the ECU, the ECU will still see it as an old battery, you run the risk of over charging it and other running complications.
Super Member
Joined: Sep 2011
Posts: 509
Likes: 12
From: S. Cali
C63
That might not be a solution, the issue is with many modern cars is the ECU adjusts the battery charging voltage, drain on battery when starting etc over the life cycle of the battery.
When you install a new battery without reseting the battery in the ECU, the ECU will still see it as an old battery, you run the risk of over charging it and other running complications.
When you install a new battery without reseting the battery in the ECU, the ECU will still see it as an old battery, you run the risk of over charging it and other running complications.
Junior Member
Joined: Oct 2017
Posts: 68
Likes: 2
2018 Audi S6
Porsche calls for that too, so apparently all German automakers. But that the ECU can overcharge an identical battery if not done is BS IMO. My take is the ECU wants to know the age of the battery primarily to know how much discharge to allow before calling off the *** (auto start stop), to avoid leaving owner stranded with too little battery power to start the engine. But also to know when to trigger the 'low battery voltage' warning for the same reason. If you want proof that 'reset' doesn't affect charging at all, why don't you see such 'reset' on battery maintainers?
Both cars and chargers get feedback from the batteries, and know exactly how to charge them. What they can't know is how many cranking amps when fully charged, which age (sulfation) reduces. Having said that, if you change the battery type or size (AH), then you need to code it, so the charging system knows which battery you have. But if you replace the battery with an identical one, I wouldn't worry if not 'reset'. But yes, it'd be nice if OBDII scanners also had the option to reset that. In fact, I need to buy one of those to reset the stupid oil change warning on my Porsche.
Both cars and chargers get feedback from the batteries, and know exactly how to charge them. What they can't know is how many cranking amps when fully charged, which age (sulfation) reduces. Having said that, if you change the battery type or size (AH), then you need to code it, so the charging system knows which battery you have. But if you replace the battery with an identical one, I wouldn't worry if not 'reset'. But yes, it'd be nice if OBDII scanners also had the option to reset that. In fact, I need to buy one of those to reset the stupid oil change warning on my Porsche.
Last edited by elp_jc; Nov 30, 2017 at 03:44 PM.
