LG 42LG60 Manual page 32

SMPS PWB Connector P401 or P402 Voltage and Resistance
SMPS PWB Connector P401 or P402 Voltage and Resistance
Caution: AC over 1Kv. Use extreme caution when reading this voltage.
Operating Frequency 54Khz.
Pins 1 and 2 are actually shorted together. (Either Plug)
Reading between P401 and P402 actually reads the Transformer T701 windings. (0.1V)
For a simple and safe test:
Place the Oscilloscope Probe along side the wire from P401 and P402 connectors
to the Ballast and a 17.5μ sec sine waveform should be measured this would be
an indication that the ballast supply is functioning.
Resistance taken in Diode Mode with Connectors Removed
P401 or P402 Backlights
Pin STBY Run
1 0V >1Kvac
2 0V >1Kvac
Diode Check
0V
0V
32
LCD DV 42LG60