2003 StreetKA has no working boot release from the remote. Other doors open and close fine but boot will not pop open as it should. Having googled it, it seems the boot solenoid are notorious for failing so got a new one and fitted it but still not working.

Solenoid isn't powering at all, though you can hear a very quiet relay clicking noise inside the car.

Is there a fuse that could have blown and if so which one?

If you can hear a relay clicking then it won't be a fuse problem.

I had this problem on a MK1 Focus.

Check the wiring in the rubber conduit near the boot hinges.

The cables get brittle and snap due to repeated bending.

Get an auto electrician to check the wiring there and I'm fairly certain that there will be a broken wire.

Didn't think the wiring on a StreetKA for the boot solenoid was routed through the hinge and instead was routed round the side of the boot under the carpet lining.

Have tested for voltage and only getting 3v maximum once the button is pressed. Could the relay be the cause? Where is it located so it can be tested.