Thanks for the replies guys.
@petey - I have been trying to contact a forum member who has a workshop near me to get my codes read but have not heard from him as yet - code reading is top of my to-do list for sure
@SimonJones - I do have another key and will use that for a while to see if the problem happens again
@DT19 - that may be a good call - my fuel is quite low as haven't been out to fill up (still shows about 100 mile range but no doubt that won't be entirely accurate)