Ericsson R250s PRO Troubleshooting Instructions page 14

If the fault still remains send the unit on according to the local company directives.
4.1.2 Earphone problems
Disassemble the phone and check for liquid damage.
No further action should be taken for a liquid damaged telephone.
Check the speaker pogo pin contact (connection between J900 at the board and the earphone).
•
Measure the resistance of the earphone in the front cover; it should be 8 ohms.
If the fault remains: Check the soldering of N800 pin26.
•
Measure the resistance between J900 pin1 and ground ~56 kohms,
pin2 and ground ~56 kohms.
If the soldering is ok: Give the board power and start it up.
•
Measure the DC voltage 3,2V (VANA) at N901 pin1,18,3,2.
4/00021-2/FEA 209 544/18 D
If not replace C815 and C816.
If the fault remains:
Check the soldering and measure the resistance of C850 >100 kohms
and C851>1 kohm.
Replace the faulty component.
If the resistance is higher replace the front cover.
If the resistance is lower, replace C909 (and C927).
If the resistance was ok.
Measure the resistance and check the soldering of R906 ~100 ohms, R914~0 ohm
R917~10 kohms, R919~10 kohms, C914~56 kohms, C913~150 kohms.
Replace the faulty component.
If all the measurements are ok:
Check the soldering of N900 and N901.
If VANA is missing at pin1,18,3,2, send the unit on according to the local company
directives.
If VANA is correct at N901 pin1,18,3,2: Measure the DC voltage 4,6V at N900 pin1.
If the level at N900 pin1 is too low or missing:
Check the soldering and the resistance of R916~33 kohms and R918~33
kohms.
Replace the faulty component.
If the fault remains:
Check the soldering and measure the resistance of C801,
C808, C814, C818, C819, C829, C830, C831, and C834. They
should be > 100 kohms each.
Replace the faulty component.
If the fault remains:
Replace V803.
Standard Trouble Shooting Instructions
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