Samsung PPM42S2X/XAA Service Manual page 71

Circuit Operation Description
19. Point Probe2 at LY1 pin1 (F2011 pin7 (YS) on the logic main board) on the jig board.
20. Point Probe2 at LX1 pin2 (F2015 pin6 (XRR) on the logic main board) on the jig board.
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