There's an electrical problem with the Amp causing an open circuit in the optical loop. Test the fuses in the rear left boot. Then test all connections on the amp.
Have you had sound in the past?
Regarding the energy management; Is the battery good / how old / has the car been sat for a long time? In a freeze frame the voltage is 10.56 V, pretty low!
Code:
1 Fault Found:
01826 - Sensor for Steering Angle (G85); Supply Voltage Terminal 30
000 - - - Intermittent
This usually appears when the battery has been disconnected.
Clear all faults. Shut down car. Wait 15 mins for it to sleep then open car and do another scan. Save. Go for a drive. Rescan then post both scans and we'll see what DTC's remain.
One of the rear lights is faulty, the Aux Heating is locked and a couple of common issues of engine mount and footwell heaters. Nothing shouts out as serious to be worried.
