[SOLVED] Two 3S as 6S weird charger behaviour


I am facing bad charger behavior when trying to use a self-made 2x 3S to 6S balance harness.

The charger is a genuine iMax B6 AC with Chea-Li firmware.

I am quite sure I set my harness up correctly as nothing is exploding and I get correct voltages when measuring the pinout that goes to the 6s plug.

Yet when I plug it to the charger to do a calibration weird readings seem to happen when measuring straight at the charger(disassembled for calibration).

The diagram I based my harness on: image

This is how my harness looks like: 07 First cell balancer first pin is black colored wire.

37 The last pin of first battery is connected to first pin of second battery both being combined on the orange cable.

All cells report good readings except for cells 3(red/orange) and 5(yellow/green).

All cells show 4.11, the same as the voltmeter, but those problematic ones show 4.26(while voltmeter at the plug shows 4.11)!

When I connect my 3S batteries normally, they show correct cell voltages.

When I connect a 4S battery, even it shows normal voltages, so it cannot be a charger issue I think…

Anybody has faced such an issue and might know what’s up?

I want to charge these lipos as a single battery! :smiley:

Apparently removing the third pin connection from the first battery balancing plug and putting it to first one of the second battery instead (3+4 instead of 4+3 and a connection in the middle) made everything work. No idea why though…