Audio Problems - Ericsson R250s PRO Troubleshooting Instructions

4 Audio problems

4.1 Type of fault
Make a call to another phone.
Check which part is faulty, (microphone, and earphone).
Switch ON manually the loudspeaker.
Check which part is faulty (microphone, loudspeaker).
If the microphone is faulty, go to the section 4.1.1 microphone problems.
If the earphone is faulty, go to the section 4.1.2 earphone problems.
If the loudspeaker is faulty, go to the section 4.1.2 earphone problems.
Connect a handsfree to the phone.
Make a call to another phone.
Check which part is faulty, the external microphone or the external earphone.
If the microphone is faulty, go to the section 4.1.3 hands free problems (microphone).
If the earphone is faulty, go to the section 4.1.4 hands free problems (earphone).
If the hands free is not detected, go to the section 4.1.5 hands free can not be detected.
If you can communicate with a handsfree, but you can not communicate without a handsfree, go
to the section 4.1.6 microphone and earphone problems.
If the sound is disturbed or noisy, go to the section 4.1.7 noisy sound.
If the mute function does not operate, proceed the section 4.1.8 mute problems.
4.1.1 Microphone problems
Disassemble the phone and check for liquid damage, especially around X830.
No further action should be taken for a liquid damaged telephone.
Replace the microphone and the elastomer.
Check the soldering of N800 pin 13 to pin 18.
•
Check the soldering and measure the resistance of R809, R810, R811, R812, R813, R814,
R816, R817 and R820.
4/00021-2/FEA 209 544/18 D
Replace the faulty component.
If the resistance of R820 is too low after it has been replaced, replace V805 and C832.
If the fault remains:
Check the resistance of R818>10 kohms, if not replace R818 and C820.
If all the resistances are OK. Check the soldering and measure the resistance of C815.It
should be > 50 kohms.
Standard Trouble Shooting Instructions
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