Ericsson R250s PRO Troubleshooting Instructions page 17

If the fault still remains send the unit on according to the local company directives.
4.1.7 Music mute problems
Check the system connector of the phone visually (if its damaged, dust...).
Disassemble the phone and check for liquid damage, especially at the system connector-pads.
No further action should be taken for a liquid damaged telephone.
Check the soldering of D600 pin69.
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If the soldering is ok, measure the resistance of R602~470 ohms.
If the fault remains, send the unit on according to the local company directives.
4/00021-2/FEA 209 544/18 D
If the VDSPC is low and the resistance between VDSPC and ground is
<10kohms, replace the components one by one and check the resistance after
each replacement: C903, C904, C905, R727, N701 and D900.
If the VDSPC is low and the resistance between VDSPC and ground is
>10kohms, replace the components one by one and check the 10 kohms after
each replacement of V703, R727 and N701.
If the VDSPC is correct
Switch off the board, check the soldering of D600 and D900,
if they are ok, replace D600 and D900.
If R602 is ok, measure the resistance between J602 pin6 (MUTE) and ground.
If the resistance is <100 kohms, replace F605.
If the resistance is nearly 100 kohms, replace D600.
Standard Trouble Shooting Instructions
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