The wiring looks a little scary honestly. Is that duct tape?
The blue and white connectors look like they could have been for a missing navigation computer as I do see a ibus wire (white with a gray trace and a yellow band) in there.
It is probably time to look into the aftermarket Android head units to replace your system. They are self contained and don't need any of the components in the rear other than the amplifier. More features than the factory system ever offered and the cost is probably going to be far less.