Volvo Repair: S70 trunk lock works only with key, latch assembly, failure point

Question
My S70 trunk will not open without the key.  I let my
brother open the trunk without telling him to press the button so he used the key.
I have tried to turn the key left and then back to horizonal but it does not work..  When I turn it counterclockwise and then back,it thumps so it may be by passing the unlock.
Any advice will be appreciated.  otherwise I must go to the dealer.
Thanks
Terry

Answer
Does the electrical button still work?  Pull the lining off of the trunk lid (just pop the clips off) and then look inside and tell me are any of the pushrod mechanisms come off?  If you have the tools you may want to unbolt the assembly and pull it out and look at the lock plunger to verify if its broken.  If it is you'll have to order a replacement.  Most likely something has popped off or a cable has broken.  Otherwise I would suspect that your latch assembly has gone bad, it is the most common failure point for that car.  Hope that helps.

James