Loopkey and Besttech D596 BMS BROKEN eswitch problem

So i appear to be having the same problem as most others who have one of the new BMS from Besttech. The E-Switch has failed within 1mile of getting my battery back in my board…


I have had advice from @pjotr47 but i dont want to bother him with everything as he is so helpful.

Backgrounds info… I have a 12s4p, Unity, bestech BMS

It appears the e-switch is broken/blown within 1 mile of riding !!!

The power switch will only work when i plug in the charger.

So my questions for anybody who is an expert…

1- i need to change the battery to discharge directly. (cut negative wire (1), open wire casing (wire 2) solder to wire 1 to wire 2. (now i will have direct discharge.)

What im confused by;

2- do i need a loopkey for direct discharge?? -------- most people say unessesary and Andy87(loopkey) says he doesnt bother with 1… sounds unessesary???

3- Do i need to do anything with the eswitch wire on the BMS? cut it and leave or connect it only when charging?(considering it will be direct discharge circuit now?

its question 3 im really struggling to find clear info on…

I already told you privately, lets first open battery and check e-switch wires. maybe solder joint broke, maybe one wire disconnected from pcb, maybe there is really easy fix.

  1. you have unity, you don’t need loopkey, because unity had integrated switch. only purpose of loop key is to turn your board off.

  2. those e-switch wires has to be connected when charging battery, answer is no, there is no way to just let them be disconnected.

if only e-switch wires are broken/disconnected, there is no need to bypass battery to charge only. but there is also no reason not to do it.

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thanks for the advice man, your always extremely helpful and fast to respond.

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