Ericsson GF 768 Troubleshooting Manual page 22

Troubleshooting guide
When you've repaired the fault you need to verify the charging function as described in 4.1.1.
4.4 Starts, doesn't charge but indicates charging.
Open the phone and check for water damage, especially at the system connector. If the gold plating is damaged
like in fig. 4.4 the board is to be discarded.
Measure the resistance from DCIO to VBATT (~390 ohms, fig. 4.5).
• If the resistance is too high, measure the resistances of R458 (class B, ~0.1 ohms, fig. 4.2) and R455 (class A,
~390 ohms, fig. 4.2). If they are correct, measure the resistance from DCIO to the marked side of R455 (~0
ohms). If it's too high there's a foil damage and the phone is to be discarded.
Check the resistance from GND (pad 10) to AGND (pad 4, both of them in fig. 4.5) at the system connector pads
(~0 ohms). If it's too high there's a foil damage and the phone is to be discarded.
If the fault remains, send the phone to the next level.
When you've repaired the fault you need to verify the charging function as described in 4.1.1.
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