exactly....anything below 2019 seems to fluster the the whole system.
When I replaced my BBS02 for an HD I swapped the motors, everything went perfectly. The next day I packed my trailer for a long ride, food, drink, toys, a recliner, about 100 lbs of gear with the front panniers. I charged the pack to 56.8V / 86% capacity (my standard charge), and the spare pack to 58V because I thought I would be doing a minimum of 100 miles loaded. The day was beautiful, I was enjoying it so much that I rode about 65 miles and still had voltage to work with. I don't deplete my packs past 45.4V / 20% and I was still above 50V. I knew I had a full pack and thought it might be nice to splurge on the way home... so I kept riding until I hit 20% capacity. I stopped, got out a small folding stool, a little pot, some grapes, opened up the trailer, and replaced the two packs. Put everything away smiling, basking in the glow of the perfect day, and then... nothing. There was no throttle, there was no assist, the display came on and showed my precious 58V sitting there begging to be used, and nothing. So where do you start troubleshooting first? I pulled the used pack out of the trailer, reconnected it and everything worked fine. Scratched my head and smoked another hit tried to think of anything else to test, and then started grinding home. The shortest route was 30+ miles with a massive incline and heavy traffic the whole way, so I saved those precious few last volts to get up the b**ch, stopped 4 times,
had to stop 4 times. The whole way I was thinking about the full pack in the trailer, pissed off, wondering if I should stop and troubleshoot it again for the 4th time. The next day I called California ebikes where I bought the BBSHD and explained what was happening. BaFang had a full run of controllers that would lockout if the input voltage was at 58V. So, yeah. At least I knew what it was at that point. Doug shipped a new controller and gasket express, swapped it out with the brand new controller that came with the motor, and have been riding it since, over 25K miles, and hoping for another 6K this year.
https://photos.app.goo.gl/G5bHVMQDH4wxP4rB7