I had same problem with my 2002 Zafira, basically you can hear the motor running but the lock is stuck.
I've tried everything I can to get it to open, but to no avail, then for no reason it will open, but won't close!
Basically you need to take it into vauxhall (which will cost close on 300 for them just to look at it) and they will replace/repair as necessary, you may have gunk stuck around the lock, or the lock has "dried" as in there is no lubricant on it.
It could be a major problem, but in the same instance it could be a minor one.
As your car is still under 2 years old, surely it's still covered under the manufacturers warranty?
Hope I've been some help. Let us know how you get along!
Fiona
December 2010
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