My Zapino has dropped from a 20+ mile range to a 9 mile range. I have 1250 miles on the scooter. I also use the standard 60 v smart string charger that came with the 2008 scooters. After taking all the body panels off and flipped the circuit breaker to the controller off I checked each battery in the series separately with a battery tester with a load. Every battery started with a 13.2 V reading then went to a 11.4 v reading under load. After turning the load off, it went to a 12.8 v reading. While this all fell within what I think would be good and balanced batteries I was surprised that all the batteries checked out the exact same (and all good). With the exception of turning off the circuit breaker, I left the batteries all connected. When testing I hooked the leads directly to the battery terminals of each battery.
Was this the correct way to test the batteries? Did I interpret the results correctly? Any additional advice on battery testing and/or troubleshooting?
Thanks in advance for any advice.