Thanks for the information and details from tech report. First case I am aware of that apparently a software update and cell balancing themselves fixed problem of losing SoC daily. Perhaps updating "Battery Control Module" software, the ecu that sits at the top of the 'E-box', was the primary fix for the battery problem.Two months later and the Taycan is back home! Apparently all fixed. The solution? A complete reinstall and upgrade giving my 2020 Taycan 4S the software of the latest 2025 model. The latest battery management software has (according to them) completely reset the battery cell that was previously “out of wack” (initially by 6% and at its worst by 23%). Now it’s completely balanced with the others. Road tests show a real life range of about 220 miles; it’s reporting 258 from 98% (which for an old car with 58K miles is considered pretty good by Technical.)
It’s a different car now. Software updates to just about all systems plus the brake recall means it drives and recuperates like 2025 models - massive improvement in braking. The journey back from the Porsche centre always took 10% charge previously- today the same journey took 6%. Apparently steering, PSM and everything else is also upgraded- less noticeable but it does feel a bit more sporty.
The key symptom I was seeing previously of the battery being heated to 30C most of the time (which I personally think was causing the huge battery drain while parked and reduced range) has now gone. It first began after a new heater and pcm upgrade. Now the 2025 software seems to have resolved it…. I hope!
Apparently my car may be quite rare right now: a 2020 4S running 2025 model software. I’ll report more on what I notice if anyone is interested!
They claimed it took just one drive after the update for the batteries to rebalance themselves.
But this is massive news. This basically 100% confirms that porsche can update j1 models to J1.2 model software; and they are not doing it.Two months later and the Taycan is back home! Apparently all fixed. The solution? A complete reinstall and upgrade giving my 2020 Taycan 4S the software of the latest 2025 model. The latest battery management software has (according to them) completely reset the battery cell that was previously “out of wack” (initially by 6% and at its worst by 23%). Now it’s completely balanced with the others. Road tests show a real life range of about 220 miles; it’s reporting 258 from 98% (which for an old car with 58K miles is considered pretty good by Technical.)
It’s a different car now. Software updates to just about all systems plus the brake recall means it drives and recuperates like 2025 models - massive improvement in braking. The journey back from the Porsche centre always took 10% charge previously- today the same journey took 6%. Apparently steering, PSM and everything else is also upgraded- less noticeable but it does feel a bit more sporty.
The key symptom I was seeing previously of the battery being heated to 30C most of the time (which I personally think was causing the huge battery drain while parked and reduced range) has now gone. It first began after a new heater and pcm upgrade. Now the 2025 software seems to have resolved it…. I hope!
Apparently my car may be quite rare right now: a 2020 4S running 2025 model software. I’ll report more on what I notice if anyone is interested!
Seeing as it works, and they allow you to drive it, witch their name behind the fix; I'm pretty sure it is designed for it, and they are told not to do it because they need every bit of reasons for people to buy the facelift.
Did you find any new user interface with the new SW? Did the displays change to show the 2025 displays or just stay? Do you have any idea if the updated all the Software in all the 100+ ECU’s or just the BMS software?
