Ericsson T18s Trouble-Shooting Instruction page 56

Measure the voltage at pin 3 of V620 (~4.8V, fig. 9.5).
• If the voltage is missing, replace R685 (class A, fig. 9.5).
Also measure the voltage at pin 2 of V622 (~3.2 V, fig. 9.5).
• If the voltage is missing there's a foil damage.
If both the voltages are correct, short circuit pin 2 and 3 of V620. That should start
the vibrator.
• If the vibrator doesn't start, check the solderings of X680 (fig. 9.5) and try with a
vibrator that you know work.
• If the vibrator starts (when short circuiting V620), try to ground pin 1 of V622.
* If the vibrator starts, measure the resistance from pin 1 of V622 to D600 pin
45.
* If the resistance is more than 10 ohms, measure the resistance of R611
(0 ohms, class A, fig. 9.5).
* If the resistance is correct there's a foil damage and the phone is to be
discarded.
4/00021-2/FEA 209 544/12.B
T18s, T18sc Standard Electrical Repairs
Fig. 9.5
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