-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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41 pin 4 wafer motorised function switch is driving me round the twist. Desoldered from the board and low voltage driving the motor to each of the six points where the first wafer switch , on in each of 6 positions, the one with narrow contact areas, is closed at dead centre of each 6 detents. Then each of the 3 corresponding wafers checks out ok. But solder the damn thing back in and the relative positions move. If the second wafer that sends 5V from the common via one of the 6 switch positions to the pic chip is not making, so not sending 5V to the processor, then both the function select and the volume control cease to function as both control lines to both motor drivers go down. Until you manually fiddle with the function switch and contact is made again.