1995 BMW 325 Overheating

As to the cooling system, when I am bleeding the air from the cooling system I take the bleeder screw completely out and fill the system, then screw the bleeder back in and start the car, inspect for flow through the bypass by looking in the filler neck, there should be a steady stream. Reinstall the pressure cap and allow to come to operating temperature with the heater on maximum, then a test drive and allow the engine to rev to 4k rpms and hold it steady for a minute or two. Then allow the car to cool and readjust coolant level if needed. As to the radio code, I'm assuming you have the code in hand and have tried it and it didn't work, if so you will need to leave the radio on for half an hour to get past the security lockout and try it again. If you are wondering how to key the code into the radio, use the preset buttons. If the code is unknown, remove the radio and record the serial number, BMW can give you the code from that.