Ericsson R250s PRO Troubleshooting Instructions page 15

If the fault still remains send the unit on according to the local company directives.
4.1.3 Hands free problems (microphone)
Check visually the system connector of the phone (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 N800, pin19.
•
Measure the resistance of R825~3,3 kohms, R830~470 ohms, R802~3,9 kohms, and
R805~15 kohms.
If the fault remains send the unit on according to the local company directives.
4.1.4 Hands free problems (earphone)
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 N800, pin22.
•
Measure the resistance of R804.
If the fault remains send the unit on according to the local company directives.
4/00021-2/FEA 209 544/18 D
If R916 and R918 are ok:
Replace the components C919, V901, N900 one by one. After each
replacement, give the phone power and start it up and check the DC
voltage 4,6V at N900 pin1
If the DC voltage 4,6V at N900 pin1 is correct:
Replace N900 and N901.
Replace the faulty component.
If all the resistances are ok:
Measure the resistance of C835 >1kohm,C817 >100 kohms, C810 >10 kohms and
C812 >100 kohms.
Replace the faulty component.
If it is lower than 50 kohms, replace F601 and R804.
If the fault remains, measure the resistance of R806~100 ohms.
If R806 is ok, measure the resistance of C813 >100 kohms.
Standard Trouble Shooting Instructions
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