Hi Holger.
I have done a bit of testing on our own R1150GS - as you know a model very similar to your own. The short answer with regards to your TPS-Idle Switch question? What you seeing is normal - if I understand your description correctly. That's the way it should work. Bonus: once you dig into the details, it actually makes sense.
The bike has an "idle switch" (also known as a "choke") on the left handle - you know this, but stating it as a fact for those that dont or have forgotten. The reported "idle switch" monitors the position of the butterfly, not the switch. So if the butterfly is opened using the "idle switch/choke", the status reports ON. The status also reports ON if the bike butterfly is opened using the TPS. The reported "idle switch ON/OFF" is thus really the status of the "sensor" measuring the position of the butterfly as being closed or not - if you like. It gives you feedback on the position of the butterfly's position". ON implies the butterfly is not fully "closed", but rather slightly (or very much) actuated. OFF means it is closed proper! (For the sake of others: note that the GS-911 reports both the Throttle Position Sensor and the Idle Switch - these should not be confused. They are not the same thing. The idle switch said completely "closed/OFF" or "opened/ON". The TPS says open by how much.)
Like our CEO (Stephan Thiel) wrote back in 2010: "naturally if the cable to this switch is too tight, OR if the throttle is not fully released (due to friction devices or lack of free play) OR a TPS that is set horribly wrong... then the ECU will NOT see the idle switch as OFF..." - from
https://groups.google.com/forum/#!topic/gs-911/kPDPc5qzf1k“There is definitively some kind of “idle switch” function present in the TPS unit, or to be exactly, it’s calculated by the MA2.4 from the TPS position, so it’s not a hardware switch. The MA2.4 knows when you close the throttle as it cuts off fuel until 2000 rpm when braking on the engine for example.” - Jos in the same thread.
Does that make sense? If anyone else has any feedback, please feel free to correct or clarify my statement.
With thanks
Nicol