This unit has no coding or protection issues – so will be a straight refit. No sound after repair will usually be down to the fact that there is no 12v supply to the amplifier, as the unit suffers from loud random noise , we usually find that the fuse has been pulled from the fusebox – it’s easier to do this than unplug the amp.
The unit itself has no fuse on the housing – the only fuse is the one in the fusebox.
Occasionally we find that people forget to plug all 3 plugs back into the unit – ensure both black and the one green plug are firmly inserted.
Also with certain units ( depending on year of car ) – the data line to the amp goes short to ground , this is due to the headunit being affected by amplifier failure – the remedy of this is to cut the white (usually) wire going to pin 10 on the smallest plug …. it’s the bottom left , second wire in .
If this resolves the issue with no sound , then you can send the headunit up for us to repair.