Hi Schuppi,
I've had chance to look a bit deeper into my Hall Effect Sensor Error.
The wiring checks out, I used a pin in the wire between the ESA connector and the ESA unit on the shock and it all meters out good.
I also have a 2013 GSA with fully functional ESA fitted, I didn't go as far as removing the GSA rear shock to test it plugged into my K16 electronics, but it did give me some comparitve readings.
What I do know. Firstly, the stepper motor white plug for the damping. On both bikes, this meters out at around 40 ohms across both pairs of coils, so pretty happy that this is all ok. On the pre-load black plug, the outer two wires to the motor I conected a 12v battery to the other day and could wind the pre-load all the way down and back up, so I know the pre-load motor is good.
With the bike running, I can change between 'soft', 'normal' and 'sport', and the front end changes as it should, the rear however doesn't change at all, peobably as you mentioned in an earlier post the rear end is disabled as it is seeing an error.
This just leaves the two centre wires of the black plug for the Hall Effect Sensor.
Using my meter on 'diode' test range, my GSA was giving me 0.8 (volt drop) one way, and if I reversed the leads 1.9 the other way across the sensor. On my K1600, I was getting open circuit both ways. The supply going to one side of the hall effect sensor was around 8v on my GSA, but 12v on my K1600. I did read somewhere that anything from around 5v to 15v is a typical hall effect sensor supply voltage.
This is bringing me to the conclusion that the actual hall effect sensor in the ESA unit itself has gone, but not having an identical bike / ESA shock to compare it against I can't say for certain. It was interesting that the 2011 K1600 has a supply of 12v to the hall sensor, but my 2013 GSA has an 8v supply. Makes me wonder if the hall efect supply voltage has been turned down on the later bikes / software to improve component reliability?
I'm thinking that the next step may be a visit to the BMW dealer, see if their diagnostics / testing can go any deeper or if an ESA controller re-flash / upgrade has an outside chance to resolve it? When I interrogate the ESA with my GS-911, in the serial number field I get a row of strange characters, something like this ( ?* !. * ?-!). Which makes me think there could be some firmware corruption here.
Although in my mind it's all pointing towards the sensor, I want to be 100% certain before spending a load of money on a new shock.
Appreciate your thoughts on this.
Many Thanks,
Roy.