Quote:
Originally Posted by HPsauce
Knowing little or nothing about how these gearboxes work and are controlled I'm nonetheless a bit surprised by that.
I had assumed it was taking physical information about the state of the gearbox and relaying that electrically to the TCU. 
If it's just the physical position of the gear selector lever, why not detect that in the cabin? Or is it to eliminate the possibility of a loose/worn mechanical link (cable?) and get the information "from the horses mouth" so to speak, i.e. as close to the gearbox as possible.
Or is there a belt and braces approach, with sensors on the lever as well? There obviously are for the tiptronic elements. |
The tiptronic switches are on the gear selector, but the F125 does everything else. I can't see any reason why it couldn't be in the selector tbh.
The F125 tells the TCU which gear is selected, and the shift lever also has mechanical functions inside such as engaging the parking lock and interacting with the valve block. The cause of PRNDS in this case is the TCU not getting sensible signals from the F125, rather than any feedback from gubbins inside the gearbox (like the speed sensors etc).