!. does the motor make a noise or is it just dead (mine currently makes a release type noise but does not open the boot, must be mechanical and in the boot rather than electrics
2. Lighter can be tricky, are you trying with a satnav lead or the lighter itself? Changers do not seem to work too well, seems too recessed to work. The radio is on the same circuit, so not likely to be a fuse
3. Common fault (and still not fixed on the 147) water gets in causing the spindle to rust and seize up. It can be dismantled, cleaned, greased and re-assembled OK. Ones of a breaker are likely to be the same as the newset car is 12 years old.
HTH and enjoy