8 blinks of a LED suggests there is an AV failure.
I suggest you recheck the AV (scart) board, the most likely component failure is the IC which regulates the power on the board.
The video here may be useful, to identify where the IC is, failing that I would look to replace the entire AV board.
If the unit has been services by Pioneer service centre they wouldnt let it leave the shop with this fault.
I will opt out in favour for another expert, but think you need to revisit the service centre under their warranty period.