I can't fathom the reasoning for disabling TR if the steering solenoid isn't operational, as its only used to make the steering lighter when parking and at slow travel speeds. However with no other indication of a fault, it was a prompt to check for fault codes. GGS was in use so TR being disabled was immediately noticed, although a message indicating the failed steering solenoid would have been much better.

Codes B12FB-14 and B12FB-1F were for open or short circuit for the steering solenoid, caused by a broken wire near the solenoid. The insulation on the other solenoid wire had worn through so that wire needed repairing too. My diagnostic tool is as much a part of my tool-box as the spanners and soldering iron.