3-4
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
2. NO BOOTING WHEN POWER ON THE SET
The set doesn’t work when press the power button on the top board or the remote control.
2-1. IC501
2-1-1. Solution
Replace IC501 on MAIN board.
2-1-2. How to troubleshoot (Countermeasure)
1) Check the +12 V (CN201) and 3.3 VA (IC202) in standby mode.
If there is no 12 VA, check the SMPS and if doesn’t appear 3.3 VA, check IC202.
2) Check +12 V, +5.1 VA, 3.3 VA, DVCC_5V and DVCC_3.3V when power on the set.
- If the set doesn’t work regardless of what the KEY1 changes high to low while pressing the power button.
X500 and X501 work normally but, if you can not power on the set, replace the IC501 with a new one
on the main board.
2-1-3. Service hint (Any picture/ Remark)
< MAIN board top view >
< MAIN board bottom view >
X500
X500
(24 MHz)
(24 MHz)
X501
X501
(32.768 kHz)
(32.768 kHz)
IC501
IC501
R5B78
R5B78
PWR_CTRL
PWR_CTRL
