Sound Signal Circuit between Video Terminal and Television Display: Procedure
- CHECK HARNESS AND CONNECTOR (TELEVISION DISPLAY ASSEMBLY - VIDEO TERMINAL)
- Disconnect the television display assembly and video terminal connectors.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
Tester Connection Condition Specified Condition Q13-7 (AUXR) - O25-1 (VAR+) Always Below 1 Ω Q13-8 (AUXL) - O25-2 (VAL+) Always Below 1 Ω Q13-23 (SG7) - O25-3 (VA-) Always Below 1 Ω Q13-24 (OPEN) - O25-8 (ADPG) Always Below 1 Ω Q13-7 (AUXR) - Body ground Always 10 kΩ or higher Q13-8 (AUXL) - Body ground Always 10 kΩ or higher Q13-23 (SG7) - Body ground Always 10 kΩ or higher Q13-24 (OPEN) - Body ground Always 10 kΩ or higher
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- INSPECT VIDEO TERMINAL
- Using an oscilloscope, check the signal waveform between each terminal and body ground according to the conditions shown in the table below.
Standard conditions
Tester Connection Condition Specified Condition O25-1 (VAR+) - Body ground External device system is playing, sound is being produced Waveform synchronized with sound is output O25-2 (VAL+) - Body ground External device system is playing, sound is being produced Waveform synchronized with sound is output
NG → See step 4
OK → See step 3
- Using an oscilloscope, check the signal waveform between each terminal and body ground according to the conditions shown in the table below.
- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
- REPLACE VIDEO TERMINAL. Refer to REMOVAL