Ericsson GF 768 Troubleshooting Manual page 12

Troubleshooting guide 4/00021-2/FEA 209 544/6 C
Fig. 2.6
If voltage is missing at some keys in a row (se functional scheme fig. 2.4) there's a foil damage and the phone is to
be discarded. This is verified by measuring the resistance from the marked side of a working pad to a non-working
(~0 ohms). The foil damage is usually caused by water damage. If, for instance, there's voltage at pads 4 and 5 but
not at 6 and "volume up" there's a foil damage between keys 5 and 6 and the phone is to be discarded.
If a column or part of it is non-functional, check the solderings at D600 pads 1 and 120-128. If all of them are cor-
rect, replace D6000 (class B).
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