First, go to the bluetooth menu on your phone and delete the car from it.
Then search again for the car's bluetooth name, and try to connect. As mentioned above^the default passcode is 0000 or 1234.
It could be different, and have a look at the manual that came with the Audio player.It will explain everything in detail and you might get the correct passcode from there too!
Some times you have to hold a certain button so the device becomes searchable. Tried that yet?
and that KB-100 device is an add-on i believe. So you can place it in some convenient area and have easy access to all these functions:P Please share the price of the HU though!