LG
November 2017
55EG9600 (2015 OLED) Power Supply
TEST 3 Power Supply Board 24VD/12VT to T-CON Voltage Check
Continue if Test 1 and Test 2 were OK.
Leave jumpers (A) and (B) in place. AC Power is removed at this time.
The T-CON should be connected, SMPS P202 and P203 to T-CON.
TEST 3: T-CON 24V POWER SECTION TEST:
(3) (B) Add another jumper between (STBY_3.5V) pin 5 and (DRV_ON) Pin 2.
(See Fig. 3), Simulating PWR_ON, DRV_ON and 12V_ON command.
(4) Apply AC Power.
(5) Check 24V on pins 8-14 on P203.
T-CON 24V Normal:
a) If normal (24.16V), the SMPS is OK, T-CON load test OK.
T-CON 24V Abnormal:
a) Recheck all connections.
b) Confirm the DRV_ON line pulling up to at least 3V.
c) Check SMPS P202 pins 8-14 for an excessive load, diode check should
be “1.00V” P202 connected or “1.05V” P202 disconnected.
Check CN5 pins 8-14 on the T-CON for an excessive load, CN5 unplugged.
Diode check should be;
• “OL” (Blk lead on Gnd) Panel connected , “OL” Panel Disconnected.
• “0.36V” (Red lead on Gnd) Panel Connected, “0.54V” Panel Disconnected.
See Next page to Test the Power Supply’s T-CON 24V line
using a light bulb test jig.
TIP: If you are concerned that
you may accidently connect the
jumpers in the incorrect
locations, please use a 100 ohm
1/8W resistor instead.
Pin 1 is Bottom on SMPS
Pin 1 is Top on Main
SMPS TEST 3
Top Row pins
are Odd numbers
DRV_ON
C
Fig 1
17 18
15 16
13 14
11 12
9 10
7 8
5 6
3 4
1 2
P201
12V
12V
STBY 3.5V
24V
24V
PWR_ON
A
12V
12V_ON
B
23 24
21 22
19 20
STBY 3.5V
STBY 3.5V
12V
12V
24V
24V
Gnd
Page 06