Yamaha battery

This Yamaha battery we usually see on BH and Haibike.

It has a very similar BMS to the Shimano bikes, for sure the same company. It even has the same SMD fuse!

Discharge

The middle pin needs to be paralleled to the positive output for discharge, a bit similar to how the BILTEMA batteries can be discharged. When the battery is facing display-up, the top pin is +.

Error codes and usage info

There exists a documentation, chapter two of which is very useful. It tells you how many cycles it has done, remaining capacity, and generally what is wrong. Super useful!

SMD fuse

Exactly like on the Shimano batteries, the fuse can go with no good reason, and you have a full good battery with a dead fuse. The fuse swap is the same process as described there.

Charging port

Quite often the charger plug welds itself to the charge socket on the battery.  So far, we never managed to get it off - it needs a new socket! That can only be found on batteries that failed for something else.