Someone asked me about the procedure for doing a Hard Reset on a non - US car and I have read about the radio losing the security code . Knowing the trouble in obtaining the code I was hesitant to advise the person . Can you simply disconnect all the connectors on the head unit and proceed with the Hard Reset ?

A highly experienced person advised me that US models do not have this concern as I have done the Hard Reset myself about 5 times and have not lost the radio code . There is someone in England that needs the procedure .

 

UK cars have radio codes and it will be needed after disconnecting the battery. If the radio is original any Jag dealer in UK will give the code free, otherwise either read it directly from the eeprom with any cheapo usb reader(soldering required) or through one of these recovery services in UK(~$30).

BTW, no such thing as hard reset on an X300. Disconnecting the battery will just blank some codes, but that can be achieved with an OBD scanner. The only way to do, what could be described as 'hard reset' is through Jag diagnostic software.

Well, I suppose one could disconnect the ECU entirely, I've read somewhere that eeprom will reset itself to factory settings in ~2 years

 

For older models like X300 and earlier, the belief that radio code can be recovered from the dealer has been declared dead. Jaguar global database no longer keeps such data. See my thread Radio code recovery for older models NLA from dealers? of March 2017. The other ways of recovering the code is either paying online with your radio unit's model and serial number, or search the car for any note written down somewhere in the Owner's Handbook, marked on the radio unit cover (as in my case), or scribbled on the body such as the underside of the hood, on the pillars, etc. If you are lucky, you can ask the previous owner if he/she remembers the code, or ask the dealer where previous owners serviced the car to see if the code has been stored in the maintenance file if not already archived or destroyed... If too much trouble, buy a good used one with a valid security code, or one that doesn't need any.

 

Maybe you're right, last time I've asked for the code to my radio it was sometimes in 2016 I think.

 

FWIW here in Ireland, I got my radio code from a Jag main dealer, free gratis back in 2012.