LG LAB550H Service Manual page 44

When you turn on your set, it will display "WELCOME" on front panel, and it will not boot-up normally.
2-3. X501
2-3-1. Solution
Replace X501 on MAIN board.
2-3-2. How to troubleshoot (Countermeasure)
1) Please check the soldering status of 27 MHz crystal (X501).
2) Please check the frequency of 27 MHz crystal (X501).
3) If the crystal doesn't oscillate, replace X501.
4) After changing it, if the set is still not booting :
- Check NAND Flash IC (IC502) refer to item 2-4.
- Check DDR IC (IC503) refer to item 2-5.
- Check MT8553 IC (IC501) refer to item 2-6.
2-3-3. Service hint (Any picture / Remark)
ONE POINT REPAIR GUIDE
X501 X501
< MAIN board top view >
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