Bosch AHS 4-16 Hedge Trimmer stopped working!?

My Bosch AHS 4-16 hedge trimmer is a few years old but never given me any trouble until yesterday. I had cut half of my hedge when all of a sudden it stopped working. I thought maybe the blades had jammed or a fuse blown, but after checking, it is definitely the unit itself that no longer works when plugged in and trigger pulled. I have checked all cable connections and fuses etc, the only thing I haven't done is take the unit apart and checked the wiring or anything else inside.
Any suggestions as to what the problem may be please??