The Backlight Does Not Light Up; No Sound Is Generated/ Reproduced Sound Abnormality; Rs-232C Control Does Not Work - Sharp PN-T322B Service Manual

CHAPTER 8. TROUBLESHOOTING

4. THE BACKLIGHT DOES NOT LIGHT UP

Is there any abnormality in the inverter or related
sections?
Is there any abnormality in the connection cable?
Is there any abnormality in the LED driver PWB?
Is there any abnormality in the I/F PWB?

5. NO SOUND IS GENERATED/ REPRODUCED SOUND ABNORMALITY

Is the sound volume set to minimum or mute?
No abnormality
Is there any abnormality in the audio input signal?
Is there any abnormality in the audio cable?
No abnormality
Is there any abnormality in the external speaker and
related sections?
Is there any abnormality in the speaker cable?
Is there any abnormality in the speaker?
No abnormality
Is there any abnormality in the I/F PWB and related
sections?

6. RS-232C CONTROL DOES NOT WORK

Are the RS-232C settings of PC correct?
No abnormality
Any problem with the RS-232C cable?
No abnormality
Any defect with the I/F PWB and related devices?
Any defect with the connecting cable?
Any defect with the board?
CAUTION
You must use the RS-232C cable that is straight.
Abnormality
Replace the abnormal part with a new one.
Abnormality
Readjust and reset.
Abnormality
Replace the abnormal part with a new one.
Abnormality
Replace the abnormal part with a new one.
Abnormality
Replace the abnormal part with a new one.
Abnormality
Configure the settings of PC again.
Abnormality
Replace the abnormal part with a new one.
Abnormality
Replace the abnormal part with a new one.
Replace the I/F PWB.
PN-T321/T322B TROUBLESHOOTING
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