LG OM7550 Service Manual

3-4
ONE POINT REPAIR GUIDE
3. NO BOOTING WHEN POWER ON THE SET
The set doesn’t work when press the power button on the FRONT board or the remote control.
3-1. IC501
3-1-1. Solution
Replace IC501 on MAIN board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check the 5.6 VA (CN106) and DVCC_3.3 V (IC505) in standby mode.
 If there is no 5.6 VA, check the SMPS and if doesn’t appear 3.3 V, check IC505.
2) Check 5.6 VA, +12 V, FL+, FL-, an +39 V when power on the set.
 If the set doesn’t work regardless of what the KEY2 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.
3-1-3. 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)
KEY2
KEY2
(R526)
(R526)
R522
R522
PWR_CTRL
PWR_CTRL

LG OM7550 Specifications

General

Brand	LG
Model	OM7550
Category	Stereo System
Language	English