Airbag Light On - Causes

Hi
Recently had to investigate heater motor issue which involved removal of glove box etc, after re-assembly I now have a airbag light on on main display ( Passenger airbag appears to be activated- the disable switch for passenger bag is in the glove box and is set to enable and passenger bag disable light is off).
I have an OBD wifi adpater/Torque Lite phone App - no ECU fault codes reported .
Would starting car when glove box out ( passenger airbag de-activated) cause some weird ECU condition which might explain the fault light ?
Any merit in disconnecting battery to get ECU to go through a clean power up ?

If you turned the ignition on with the passenger airbag switch disconnected it would have stored a fault code. You will need a scanner to clear the code.