hi looks like was the tcs light on the left side of the dash
Morning Bill et al...
The TCS system in interconnected with the ECU, as such it is connected to the ignition (retards the spark and thus reduces power to the rear wheel), and it gets its information from the Halls effect sensor on the rear wheel.
Unlike the ABS, the TCS, doesnt produce fault codes and if it faults it automatically switches to the standard ignition system. So, yes the TCS interconnects with the ECU to produce its unique ignition system, but if it fails it (the TCS), releases the ignition to the ECU.
So, IF it is in fact the TCS fault lamp you saw illuminate you will need to get the bike to a dealer that can diagnose the TCS/ECU connection.
You could try switching off the TCS...checking the hall sensor has the appropriate air gap at the rear wheel....check that the correct 160x70x17 tyre is fitted to begin with.
Hope this helps.
Cheers the can :-)