Right i used one of those cleaning discs today & the old disc now works, however when i put the new disc in i get a message saying " Loading please wait ", well I've waited & waited & waited for over an hour, nothing happens, i got the disc from satnavdiscsale.com they seem quit genuine, have emailed them but no response yet.
No wait i tell a lie.
Just had this reply, i will try it tomorrow & keep you all updated
Insert DVD while engine is running
Leave for 2 minutes
Turn engine off, exit the vehicle and lock the car
Wait 5 minter
Enter the vehicle and start her up
The disc should then load up fine.