OBDMONSTER 12V Car Battery Tester Digital Alternator Tester, Check Battery Condition & Alternator Charging for Car Motorcycle

Q: Will this device support my truck?

Sorry, this battery tester bm310 is only for 12v car battery testing, NOT for trucks.

Q: I have 2 - lithium 51.2v batteries in parallel. What setting do I need to use...48v??..or 60v??

I believe you would want to use the 48v setting.

Q: The ok green light flashes but i am not getting any other indicator and followed instructions. looking to get battery state info. any advice/support?

Only the OK green light is flashing, which means the current battery voltage is in the range of 4.6v to 11.2v, and the car is in the flameout state. If the ok green light and low red light are on at the same time, which means that the current voltage is between 11.2 and 11.6v, and the battery needs to be charged in time The products are equipped with instructions, you can also get this information from the instruction. Thanks for asking, hope this help.