Thanks for the very good info, however way over my knowledge of testing, batteries are two years old and we ride a lot in spring through summer and fall. I have noticed quite a difference when I pull the cart with the puppy .
HarryS gives the best advice. There's nothing mysterious about using the meter he suggested. IMO it a critical tool and very easy to implement and learn how to use. I came to eBikes from a career as a horticultural director. ZERO electrical background except for using sprinkler controls. A WATT METER AND A MULTIMETER CAN SAVE A LOT OF HEADACHES AND ENABLE OTHERS TO HELP YOU SORT ISSUES.