27 Oct 2008, 10:01
Hi Mike.
Working on MkIIIs and MkIVs is quite tricky. It is very easy to destroy a working module. The IC's wire bonds are exposed, as are the wire bonds on the display. The circuit diagrams you have been looking at on the other site are for MkIs and MkIIs, and are generally not applicable in your situation. The solar cell connection points are the same however, so no problem there. Make sure you haven't shorted any tracks or pads where you've attached the solar sell.
So, if you've touched the IC by accident, then the module is likely to be damaged, and cannot be repaired (sometimes the ICs are encapsulated, but I suspect yours is not).
If you've touched/bumped the display, then the diplay may be damaged and if so, can't be repaired either. Sometimes the display on these models is encapsulated, in which case it is more robust. If it is only the display that is damaged, then a new display can be transplanted, although this can be tricky for the un-initiated.
I suggest you do replace the resistors (1.6M and 22M), since this is all that is left. After this, if it seems to be working, with segments or digits out, then you might want to consider changing the display........of course these symptoms could point to a defective IC as well.
Good luck.
Rgds,
Andrew.