Your radio is a CLARION so please quote the model number.
CLARION are a bit of a problem to decode as the only one that can be decoded for free by Serial Number is if yours also has a BARCODE SERIAL NUMBER beginning with C7000000 + + + + . somewhere on the radio casing
(Usually found on a label with two barcodes ...the one required is the lower one )
. Other older models can be decoded by opening them up and examining the links or diodes wired on the circuit board
If yours does not have this C7000000++++ Serial Number anywhere on your radio and is not one of the older diode/link type models then you will have to pay at your Main Dealer or a Decode Specialist.or a local Car Radio / Audio Shop who carry out decodes ( The shop is usually the cheapest option) where the radio memory chip (EEPROM) will be electronically "read" and/or recoded using electronic kit (usually connecting to a laptop with EEPROM Dump reading software)