on button causes intermittent instant short (loss of power)?

Peter I haven't opened up this model but I suspect the problem is the slider connection inside has either moved (dropped perhaps) and is shorting out on one of the charging lugs. If you see my latest answer to the Remington 4386 you will see what's involved to put it right with these things. I would suspect that the opening up is probably the same,and that is first levering off the soft cover. I may be wrong though!!
All the best
MikeM

Mike Morris
April 2010