Quote:
Originally Posted by Timbucus
that implies all 9 junctions are dead?
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More likely, it implies that the common is open-circuit. If you think you have nothing to lose you could try applying a generous amount of heat for 30 seconds or a minute to the accessible common terminal of one of the dead displays to see if that 'does something'.
Before you do, it's also possible that despite your observation of vias going through the display PCB underneath the lens, the connection terminals along the edge of the display are not plated through (although they probably should be). If the connections are double sided (that is, there is a pad on both sides of the lower edge of the display) just try checking for continuity between the top side pads and the corresponding bottom side pads, especially those which are the common connections for the display cells which don't work.
The dud display cells may actually work if the top side pad and lower side pad are both soldered to the wire or pin passing through the connection holes.