Diagnosis Help Needed
:? I own a Flybo 6000 - one of those Chinese-made Smart Car look-alikes that is all electric. It has a 72 volt system with 6 12-Volt deep cycle lead acid batteries and a 110 charger. On the dashboard it has a Current Meter, which appears to show the amps being drawn (ranging from 1 - 15 and then 20,30, 40 in the RED) and a Voltage meter, which appears to give the system voltage load.
Here's the problem:
with the batteries fully charged, the Voltage meter shows about 73, and I start out driving and the car works great. Then, within a few blocks, the Votage meter begins to drop to 68, 65, even 58 and then the car stops. When it stops there is a kind of thud, as if some breaker is snapping, but I'm not sure. Then I switch the master switch off, wait about a half minute, switch it back on, and the voltage meter reports 72 again, I start to drive and the process repeats itself.
I would be forever grateful for any guidance on what the problem is and how to solve it, even if that means replacing the Chinese-made controller or whatever.
I would start by checking the batteries and your charger. Fresh off the charger six 12V batteries should be between 84V and 90V. If they have been off the charger for several hours they should be around 78V. One or more bad batteries could significantly cut your range. In addition, some controllers have a low-voltage cutoff (LVC) circuit which would kick in soon if you have at least one bad battery. To check the batteries, you will need a digital multimeter which you can get from Walmart or harborfreight tools for very cheap. You will need to carefully (do not break anything or short-circuit the batteries, etc.) gain access to all of the batteries. Using the 20 DCV setting, check each battery fresh off the charger (should be between 14-15V), just after a "long" ride, and during recharging. A bad battery will usually be much lower than the others after a long ride. While you have access to the batteries note the manufacturer, type (flooded/AGM/gel), size, and date code stamped on them. If the batteries are out of balance (more than 0.1-0.2V apart), you should go ahead and recharge each with a 12V charger (preferably a smart digital automatic unit) while you have the car partially disassembled. You can report your finding back here for additional help.
BTW, where did you get your Flybo and about how much did it cost you?