12 Clubman S brake lights not working
 

Hello. 2012 Clubman S here. After installing a passenger seat occupancy sensor bypass module, the brake lights don't work (both sides and center high). The running lights do work.

The car had a slow battery drain and was jumped and charged multiple times. The brake pedal switch seems to work fine. No blown fuses. No obvious damage to the FRM, and everything else associated with the FRM seems to work.

Can anyone point me to a free source of electrical diagrams? The shop I work at is too cheap to pay for them; I guess they think I can diagnose using the Force or telepathy or something...

Thanks in advance!