HVAC not working no AC Blowers only lights.

Help I have a L322 2005 supercharged Range Rover with a problem of not having anything work on the HVAC unit, all fuses are ok< I replaced the whole unit with no joy and even with great difficulty got a new last stage resister fitted. no joy.

Does anyone have any idea's, I'm exhausted with it all, I got a few months before winter sets in.

Take it to a garage?

Yes it costs but it is quite a technical piece of kit and they should know the system inside out.