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@Mrclopec so that answers the battery vs capacitor question - which is now 100% resolved. 4M0915169H comes up on the audi usa site listed as a capacitor but it doesn't say what vehicles it fits yet - that will probably come in time.
I re-looked at your ross-tech post trying to figure out what alternator your car is using - maybe I don't know where to look in the coding.
What is the part number for your alternator if it isn't 06E903024T?
Some of you say is correct, but this is just part of how discovery works, especially this close to a production change. Without trying to convolute this too far...there are in fact MY23 vehicles that still have the problematic 48v starter generator at address 0xCC. A couple of the MY23 vehicles I have vehicle data reports on, show they are all very late 22 builds up to October. This may very well be why 2023 vehicles are included, but anything beyond October may not. Again, time will tell. Im not using OBD11 to gather data nor do I use it for diagnosis. Most importantly, I do not have a 48V battery...
On a separate note, VH2/VH3 are not suspension dependent. Take a look at the link below where I referenced my scan in the ross-tech forums. Not only do I have active suspension, I have roll control as well... No active cooling (because no 48V battery).
The part number in the TSB is at address 0xCC. This is the belt driven starter generator for the 48v batterysystem. This part is not needed when you have the Super Capacitor. The picture of your battery shows part number 4N0 915 105 B...which is at address 0x61 (or ODIS says is at 0x21). The super capacitor part number I have in my car can also be found in my scan under address 0x61 (0x21) which is 4M0 915 169 H. Here is a pic of it where the 48v battery normally would be found.
Dumb question since I see you're in California. This is the gas SQ8 right? Also this brings up additional questions. Is there a DC DC converter? Is there a 48V system at all? Is the BSG completely deleted?
PS Active suspension is the system with active roll bars.
Last edited by angrypengu; 02-21-2023 at 04:44 AM.
You are correct that I’m in California and this is a gas model. My scan on the Ross-tech forum indicates address 0xC4 DC/DC Converter is present, so yes it has a 48v system. It would also appear based on the absence of 0xCC from my installation list and also based on PR code 9G5 and VH2 that the BSG has been deleted. Historically, air suspension and magnetic ride had always been used to describe “active suspension” but with new additional of electronic sway bars I suppose we could roll those in to the overall umbrella of “active suspension”, but they are not exclusive to that term.
Dumb question since I see you're in California. This is the gas SQ8 right? Also this brings up additional questions. Is there a DC DC converter? Is there a 48V system at all? Is the BSG completely deleted?
PS Active suspension is the system with active roll bars.
Active (adaptive) suspension and electromechanical roll stabilization are 2 different things. At least in EU.
You are correct that I’m in California and this is a gas model. My scan on the Ross-tech forum indicates address 0xC4 DC/DC Converter is present, so yes it has a 48v system. It would also appear based on the absence of 0xCC from my installation list and also based on PR code 9G5 and VH2 that the BSG has been deleted. Historically, air suspension and magnetic ride had always been used to describe “active suspension” but with new additional of electronic sway bars I suppose we could roll those in to the overall umbrella of “active suspension”, but they are not exclusive to that term.
So that's interesting. It implies then that there is a link between the 48V and the 12V system, obviously. But with the deletion of the BSG that implies quite a few....implications:
1) Without a BSG, what is the purpose of the super capacitor? The point of the BSG is to be able to restart the engine near seamlessly during SS cycles, and to add torque throughout the rev range.
2) Is there something in lieu of the BSG? If so, what is it? Using OBD11 or Ross-Tech, there should be modules to be able to poke around, namely, the "battery energy module" and the "drive motor converter". Is there live data that indicates any 'torque' being applied to whatever is in lieu of the BSG?
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And before I get ahead of myself, after answering #1/#2, I wonder if we can swap out the 48V for this super capacitor.
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In any event, if we get answers to #1 and #2, it may provide colour as to why the 48V/BSG systems on 2022- are failing. I wonder if it's a 'cycle' issue, such as when high load is put on the BSG to charge the 48V battery. My hypothesis (not based on any fact but just intuition) is the failures have something to do with 1) Age of our cars because these things didn't start failing until year 3+ and 2) Something to do with the 12V battery, DC DC converter, and the 48V BSG.
Why? Well, if you think about it, the DC DC converter continually keeps the 12V battery charged. As these 12V batteries start to age, and especially in the cold (winter now after all), I wonder if what is happening is that the DC DC converter will drain the 48V battery to keep the 12V battery charged. This then causes the BSG to go into full load mode once the car starts up in order to charge the 48V battery. Is this sustained high load the reason for failure? Is it b/c the BSG is crapping out due to not even the above but cycle count?
Yes! This is why assessing this change is important and establishes the relevance of this entire discussion!
So what is in the vehicle, for the alternator? What is the part number? The BSG has occupied that role, so if it is gone, seems like it must be a new part?
Last edited by ThomasWShea; 02-21-2023 at 06:22 AM.
02-20-2023, 06:43 PM
but it doesn't say what vehicles it fits yet - that will probably come in time. 
