Battery percentage stuck at 10%

CptPalmer

Member
I had to change a rear flat today and after getting everything mounted back up the battery is only reading 10%. I searched online for an answer and the only information I found was on stromerforum.ch. The thread indicated that the connectors under the neoprene cover need to be connected correctly for battery percentage readout. I checked all my connections and they are all mated correctly etc. Has anyone seen this or know a solution to this issue?
 

JoePah

Well-Known Member
I had to change a rear flat today and after getting everything mounted back up the battery is only reading 10%. I searched online for an answer and the only information I found was on stromerforum.ch. The thread indicated that the connectors under the neoprene cover need to be connected correctly for battery percentage readout. I checked all my connections and they are all mated correctly etc. Has anyone seen this or know a solution to this issue?
As long as you're convinced it is just an indication problem, try to reboot your bike.

Remove battery from bike and charge it.
Pull the connections you worked on, clean and reinstall.

When I bought my bike, the state of charge never went above 52% or below 48%... The dealer ended up swapping in another battery and that solved the problem.. go figure. This was the only problem I ever had with my bike after 1800 miles.. well that and squeaky brakes.
 

CptPalmer

Member
As long as you're convinced it is just an indication problem, try to reboot your bike.

Remove battery from bike and charge it.
Pull the connections you worked on, clean and reinstall.

When I bought my bike, the state of charge never went above 52% or below 48%... The dealer ended up swapping in another battery and that solved the problem.. go figure. This was the only problem I ever had with my bike after 1800 miles.. well that and squeaky brakes.
I did pull the battery on the computer with no change. I will try some of these other suggestions thanks.
 

CptPalmer

Member
No, the MAIN battery, and use the external plug to charge it.. A guy on ES did that with success.
Oh I see what you are saying. Actually the battery charges fine in the bike, no issues at all. Just after the charge is complete and you turn the computer on it will only read 10%.
 

opimax

Well-Known Member
at one time I was having lack of power issues w/Wifes ST1 , pulled out the batteries in both the display and the main battery. i disconnected all ext connections, i think 3 by the motor 2 on the handle bars , not sure of the number at each place but all ez disconnects, let sit for 30 min. this was called a "reboot" at my shop ... a little early to be 100% but hasn't happened since
 

CptPalmer

Member
at one time I was having lack of power issues w/Wifes ST1 , pulled out the batteries in both the display and the main battery. i disconnected all ext connections, i think 3 by the motor 2 on the handle bars , not sure of the number at each place but all ez disconnects, let sit for 30 min. this was called a "reboot" at my shop ... a little early to be 100% but hasn't happened since
:( Still present, talked to Stromer support and they said take it to the dealer, uggghhhh.....
 

Brambor

Well-Known Member
to try to continue Joe's question...Did you open the main BIG battery door, pull out the heavy battery, attached the dongle to the charger and battery and charged the battery this way?
 

CptPalmer

Member
to try to continue Joe's question...Did you open the main BIG battery door, pull out the heavy battery, attached the dongle to the charger and battery and charged the battery this way?
Yes, it charges fine that way. It also charges fine in the bike as well. Just gives a reading of 10% battery power is the issue.
 

lilrich1959

Member
The wiring on ST1 while neatly tucked away can be difficult to work on due to that same fact and tight clearances. Had a guy once who had a regular shop repair his back flat and bike would not operate afterward turns out the main leads (large plug three leads) from battery to motor has an intermediate plug under the battery carrier (Stromer uses a different term not at shop now to look it up) anyway they had inadvertently pulled on the plug coming out of the chainstay and disconnected the internal one. Not fun to reconnect. If either of them are loose your readings would be off. Also disconnect and reconnect the other two leads to insure they are making good contact. Remember to remove your main battery before attempting to service any connections to avoid the possibility of arching, surges or other issues. The motor controller is internal to the motor on the ST1 so inspect the wiring exiting the motor to make sure it was not damaged while repairing the flat. Finally check all connections on the display, if you changed the tire with the bike upside down (common on home repairs due to lack of repair stand) the display may have been damaged. When an issue arises suddenly after a repair the cause can usually be traced back to something that was not reassembled correctly, or damaged during the repair. It is always advised to remove the main battery when servicing any of the electrical components even unplugging the wheel to change a flat, maybe I am overly cautious in that respect but have seen too many things happen that the engineers said were designed not to happen. If all your connections are secure even the internal ones and your battery voltage reading (using a voltmeter) is in range to read full on the display. Then I would suspect the display, not overly expensive, easy to replace, cheap to ship and have been known to fail. Anyway that's my two cents worth hope it helps Cpt
 

CptPalmer

Member
I ended up dropping the bike off at the dealer today. It did cross my mind to check the connection in the bottom bracket but I did not. If that does end up being the problem I will kick myself. I believe the reason I ruled it out was when the connecton under the neoprene that leads to the BB connector in question was disconnected during my troubleshooting the display read no batt. Once reconnected the message was not present. At any rate I will hear from the dealer in the next few days and I will report what they found.
 

CptPalmer

Member
Well the dealer went through everything we talked about here. They tried a different battery with no change. They tried a different LCD still no change. Then they tried a different rear wheel and the problem went away. I am a hardware/software tester for the day job. So I more or less came to this conclusion before I dropped it at the dealer. They still have to hear back from BMC but let's call this one the controller.
 
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bluecat

Well-Known Member
From my point of view, either some wires from the motor making unforeseen contact - or the firmware is affected. More likely, it's the firmware. Does reinstalling make any change? Not only to the battery gauge, but also to BOOST or torque sensor settings?
 

CptPalmer

Member
From my point of view, either some wires from the motor making unforeseen contact - or the firmware is affected. More likely, it's the firmware. Does reinstalling make any change? Not only to the battery gauge, but also to BOOST or torque sensor settings?
I don't know if the dealer played with the firmware or not. If it was firmware then there would be a lot of bikes with this issue so I do would not put my money there. This is very likely hardware related and not firmware.
 

Cuong Tran

New Member
I had the some problem with my ST1 platinum. It show that it had 10% charge after I charge it for 2 nights. Took it in to the dealer door step. I turn the display on and it showed 100% go figure!! :confused: If you can give an update o what you fine out. I would like to know or the future what to do.