low battery leading to no use of GS911

[TRJeff]

2022 R1250 GS standing voltage at battery 12.8 vdc, turn on bike drops to 12.4 vdc and under bike does start if  done right away. GS 911 will not do anything saying add battery charger.  starting bike voltage drops to 8.8vdc (BMW dealer says no issue all 1250 GS bike the same)  use battery charger and still cannot keep 12.5 or higher with ignition on not started. bike running bike is charging at 14.4  vdc.  battery has been load tested by 2 different shops plus BMW dealer and all have said battery is in very good shape.  Help

[WayneC]

I have not looked at the 2022 R1250GS in detail but I would be looking for a larger capacity battery & would only fit a Lithium battery, they maintain voltage during start far better than any Lead Acid battery, 9V is the normally accepted minimum the minimum in automotive systems

Re diagnosis, for the bikes BMW specify minimum 13.5v & for the cars 14v, below that some diagnosis routines will fail, that is set by the firmware in the ECU's not by the GS911 & I am aware that even on one of the older models I have worked with simply resetting service spanner requires 14v as the reset routine in the ECU fails without 14v

In workshops power supplies, not chargers are used & are critical when programming vehicles due to the test routines done as ECU's are updated, where 14v is not maintained the ECU updating can report failures