Ericsson T28S Troubleshooting Manual page 26

9.3 Vibrator does not work
Open the phone and check for liquid damage.
Make sure:
•
There is no cable breakage.
•
The connector is not damaged or incorrectly mounted.
•
X680 is not dirty or damaged.
Power up the board and start it by pressing the ON/Off key.
Measure the voltage at pin 2 of V621 (3.70 ± 0.05 V).
If the voltage is incorrect there is a foil damage, send the unit on according to the local
company directives.
Measure the voltage at pin 3 of V623 (3.65 ± 0.05 V).
If the voltage is incorrect, measure the resistance of R683 (100 kohms).
If the resistance is incorrect, replace R683.
If the voltage at pin 3 of V621 is correct, replace V621 and V623. Make sure R627, R628 and
C681 are mounted and correctly soldered. Measure the resistance of R682 (1 kohm).
If the resistance is incorrect, replace R682.
If the fault remains, send the unit on according to the local company directives.
4/00021-2/FEA 209 544/19 E
Fig.9.1
Trouble Shooting Guide, Standard
26(29)