I have recently bought a 2012/2013 Kalkhoff Agattu C11 Impulse Premium. I know there are potential mechanical issues with these Impulse motors but that side of the bike seems to be fine and it rides really well with plenty of power assistance, not surprising really, as it shows only a little over 500 miles total use since new. It has been completely unused since 2019. In all respects, the bike is just like it came out of the showroom! The battery was showing 100% full and 100% capacity when I brought it home, although I have no idea when it was last charged.
I have done a few test rides, probably 10 miles with some steep hills, battery content had dropped by 1 LED so I put the battery on the charging cradle - there was a brief flicker of the battery LEDs when I connected it but the green light stayed on the charger. I left it for a couple of hours but nothing happened, the content level stayed at 4 LEDs, i.e. the battery is not being charged. Repeated this with the charger directly connected to the battery - same result.
I have checked the battery externally with a meter, the pins are un-numbered but referring to the charger cradle as pin 1 on the right, 1-2 is 36.4V, 1-3 is 2.8V, 1-4 is 2.8V and 1-5 is 0V.
I also checked the cradle with a meter; 1-2 is 0V, 1-5 is 4.8V ( there are only three pins on the cradle).
I think the charger is supposed to handshake with the BMS in the battery and then initiate charging - is that the flicker of the battery LEDs?
Looks like the handshake is failing. If so, why? Duff cell? If there is a failing cell or group of cells, wouldn't the battery performance be affected? The battery seems to be doing its job OK.
I've seen mention on this forum of a thermal fuse on the BMS board, is that a possibility? Or a duff BMS board?
What should my next troubleshooting move be? Dismantle the battery to check the cells or cell groups? Does anyone have map of the access points to test these?
Thanks for taking the trouble to read this, any help would be welcome!
I have done a few test rides, probably 10 miles with some steep hills, battery content had dropped by 1 LED so I put the battery on the charging cradle - there was a brief flicker of the battery LEDs when I connected it but the green light stayed on the charger. I left it for a couple of hours but nothing happened, the content level stayed at 4 LEDs, i.e. the battery is not being charged. Repeated this with the charger directly connected to the battery - same result.
I have checked the battery externally with a meter, the pins are un-numbered but referring to the charger cradle as pin 1 on the right, 1-2 is 36.4V, 1-3 is 2.8V, 1-4 is 2.8V and 1-5 is 0V.
I also checked the cradle with a meter; 1-2 is 0V, 1-5 is 4.8V ( there are only three pins on the cradle).
I think the charger is supposed to handshake with the BMS in the battery and then initiate charging - is that the flicker of the battery LEDs?
Looks like the handshake is failing. If so, why? Duff cell? If there is a failing cell or group of cells, wouldn't the battery performance be affected? The battery seems to be doing its job OK.
I've seen mention on this forum of a thermal fuse on the BMS board, is that a possibility? Or a duff BMS board?
What should my next troubleshooting move be? Dismantle the battery to check the cells or cell groups? Does anyone have map of the access points to test these?
Thanks for taking the trouble to read this, any help would be welcome!
