Recent content by Mekanix

The battery packs on these are wired in parallel, so you’re really just increasing runtime, not voltage. The bigger issue you’re likely running into is the BMS inside each pack. Even if you try to bench charge them, the BMS may already have locked things out if it sees the pack is out of...

Did you end up putting your own controllers in with your own panel?

I have been reading all your diagnostics, great work and thanks for sharing with the community. Have you tried ditching the VCM and unknown drive controllers for anything more favorable?

E702 — Cell Under Voltage Protection 1 (CUVP1) The BMS has detected a cell voltage below 2.7V for 3 seconds. Possible causes: unbalanced cells, rapid discharge of the battery. What to do: Plug in the charger. This is the first and often only step — the BMS is seeing at least one cell that...

E702 → battery voltage problem E705 → communication problem with the battery E715 → battery refusing to charge Don't open the battery there is nothing you can do with it unless you are a battery technician. If you have removed batteries from a car or truck these are not much harder than that.

Unfortunately you cannot simply install another set of batteries in these units. Each battery pack contains a BMS that communicates with the VCM over the CAN bus, and if that communication is missing the VCM will not enable the system or allow charging. Trying to bypass that protection is...