Original well scanned manual. Got the job done. Microwave problem found & corrected. For $5 and a new magnitron from ebay, it was a cheap and good the first shot fix. Electrical schematics allowed me to mage sure every thing else was ok before cutting and order for parts. Hard to live without.
Text excerpt from page 16 (click to view)
5. Trouble Shooting Guide
-. Audio Part DHC-X200/X250
SOUND Abnormal
OPEN/CLOSE Abnormal
Check if the RY801 is OK.
No
Check if the FRONT CONTROL is OK.
No
Yes
Refer to F_RLY_CONTROL. Yes
Check if the PN402 is OK.
No
Refer to FRONT PCB. Check if the IC801 PIN(2)(4) waveform is OK. Yes No
Check if the IC801 PIN(1)(3) is OK. Yes Yes
No
Check if the CN706 is OK.
No
Check PN101E if is normally. No
Yes OK Check DSP PCB. Refer to POWER SUPPLY circuit. Yes
Check POWER SUPPLY circuit. Check if the ATAPI Cable if is normally.
Reconnect it.
No
Reconnect it. Yes
VIDEO OUT Abnormal
Check PN303 if is normally.
No
Reconnect it. Check if the VIDEO JACK is OK. Yes No
Refer to VIDEO JACK. Yes
Check if the PN303 PIN(3)(5) level is OK.
No
Check if the IC451 is OK.
No
Check if the PN303 PINS(1)(2) level is OK.(0V,5V)
No
Check if the IC451 PIN(7) is OK.
No
Yes
Yes
Replace DECK MECHA DVD. Refer to POWER SUPPLY circuit. Check if the IC102 PIN(14)(180) is OK.(MT1388)
Yes Yes Check if the IC451 PIN(2)(3) is OK.
No
No
Check if the PN101A PIN(3) to (18) waveform is OK.