Check all the connections. Pull them off and spray with electrical spray cleaner.
Also do the same with the switches. Take them out and clean and spray. If still no joy try a battery reset. Disconnect the battery for about 30 minutes. Make sure you have the radio code and the SatNav as been shut down properly.
Edd
Also do the same with the switches. Take them out and clean and spray. If still no joy try a battery reset. Disconnect the battery for about 30 minutes. Make sure you have the radio code and the SatNav as been shut down properly.
Edd