I expect to have the same problem when my ailing battery packs up.
According to pages 19 and 20 of my quickstart guide, a little picture shows the top edge of the case back divided into three similarly sized areas : one which contains the sliding on/off switch, a plain area on the other side of the same edge (opposite the speaker holes), and in between them an area containing the hinge that opens up the aerial when you use the satnav.
To remove the back, you press in the two outer areas to release catches. then you can lift the back by pulling on the gap in the middle area, near the shiny front.
The second little picture in the quickstart guide at first glance looks to be from the same viewpoint. Look at it carefully to see that the satnav is the other way up, that is you are looking at what is behind the screen.
The li-ion battery is connected to the satnav via a plug
and socket near the non-sounding side of the loudspeaker and this connection should be undone before removing the battery.
Hope this helps. Best of luck !
Eric Richards
February 2011
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