I recently purchased a DICE unit off aliexpress which worked great so I decided to get a Volvo subscription to try and download a software reload for the head unit I replaced years ago to get the lights and steering wheel function to work. Everything was easy until I tried to download to the vehicle. No matter what I did I kept getting the battery voltage too low error. I tried hooking up my trickle charger to my battery, I tried buying a new bigger battery, I tried a bigger battery charger, I tried hooking 3 batteries up together as well as having the charger on them. Nothing worked. I pulled all the fuses I didn't need to keep lights from turning on when the key was in pos II. Nothing worked. As soon as the car stopped, the voltage reading on VIDA would go from 13.8v down to 10.8volts sometimes as high as 11.0volts which is the cutoff but as soon as it cycled through the diagnostic the voltage would drop halfway through the download. I have tried searching for this issue with no luck.
I was finally able to get a successful download to the vehicle by making sure the battery was fully charged and keeping the car running throughout the download. The car shut itself off at one point and the voltage did drop for a second but I guess not before it had downloaded the software to the car. All in all it was very nerve wracking and being on the time limit of a 3 day subscription did not help but if anyone else finds themselves in this situation you could try keeping the car running.
I was finally able to get a successful download to the vehicle by making sure the battery was fully charged and keeping the car running throughout the download. The car shut itself off at one point and the voltage did drop for a second but I guess not before it had downloaded the software to the car. All in all it was very nerve wracking and being on the time limit of a 3 day subscription did not help but if anyone else finds themselves in this situation you could try keeping the car running.