Does anyone know whether reconnecting the battery with the seats disconnected and removed can cause any issues, either fault codes or airbags going off etc. I have removed the seats to access the vibrating speakers/panels behind them. Now that I have removed all of the trim panels I would like to listen to the system to see the fault is with the speakers themselves or otherwise?

 

Yes, it could throw an SES/airbag light that may require the dealer to reset. I wouldn't reconnect the battery until the seats are back in.