Based on my personal experience and what others have posted, here's what we KNOW
is wrong on the initial production lithium packages (generally the first 6 months of production of the 2021s):
1. The Magnum MMS1012 Inverter/Charger under the front passenger seat was the NON-lithium version (non "L" model), thus, does not charge lithium batteries correctly.
Fix: It needs to be replaced with the "L" model.
2. The Magnum ME-RC50 remote control located in the upper electronics locker also is the NON-lithium version.
Fix: It needs to be replaced with the ME-RC50-L model so it has the lithium profile (I called Magnum and it seems the firmware cannot be upgraded).
3. The Victron MPPT 150/35 BlueSolar Charge Controller buried in the upper electronics cabinet behind the panel was shipped with the default AGM battery charge profile.
Fix: The rotary dial setting on the bottom of the unit needs to be changed to "7" for lithium batteries.
4. The BatteryMINDer 128CEC1 Maintenance charger located under the driver's seat was not set to it's highest charging rate of 8A. This is for charging the Mercedes chassis battery off shorepower, not for the lithium house batteries.
Fix: change the setting on the top to 8A via the push button.
Note: To verify if the correct Magnum "L" versions are installed for items #1,2 above, I posted some instructions here.
Here's what else could be wrong but unconfirmed:
1. The Victron Buck-Boost DC-DC Converter (charger) under the driver's seat may also have incorrect lithium charging settings and/or excessive parasitic draw. It requires a laptop connection to verify so again, this is speculative.
In addition to above, here are some factory quality issues that have been experienced or reported for the Victron MPPT 150/35 BlueSolar Charge Controller:
1. On my 2021 unit, the "PV" + and - wires were reversed from the factory, rendering my house battery solar charging useless until I found the problem and fixed it. (The dealer couldn't find it themselves.)
2. Others have reported loose (but not necessarily reversed) wires going into the controller which reduced the charging effectiveness. Once corrected, their solar charging seemed to be operating correctly.
I addressed most of the above items myself, ahead of the recall notice, but it will be interesting to see what the dealer actually fixes. Whoever takes theirs in, please post your experience here.