LG RN7 - Page 48

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ELECTRICAL TROUBLESHOOTING GUIDE
4. POWER AMP PART CHECK
YES
YES
YES
YES
YES
YES
YES
POWER AMP PART CHECK
OK
Refer to SMPS troubleshooting.
Check each line resistor output voltage.
Replace the coil.
Check IC701
Pin29, 30, 31, 36, 37, 38 input voltage.
Check PWM modulator input
IC701 pin5, 6, 14, 15.
Check IC701, IC702
pin27, 28, 32, 35, 39, 40.
NO
NO
NO
Check CN201 pin11, 12: 12 V,
pin3, 4, 5: 58.5 V (47 V, 34.5 V)
Check IC701
pin2: AMP_12V input.
Check output line coil.