Neighbor gave me a dead LG 20" LCD monitor. After opening it up and 
running some basic voltage tests, I found the 5 volt going from the 
power supply board to the video board was a couple of tenths volts. The 
12 volt supply was OK. Checked  both the power supply and video boards 
for the usual items which were all negative including:
1: Shorts to grounds and other circuits
2: Close visual inspection for cold solder joints, bridges, and broken 
traces
3: Capacitors for shorts
4: Diodes and transistors for open/short with DMM
5: The video board 5 volt in pin to ground or other circuits was open.

Couldn't find detail info on transformer, and most chips.

Disconnected cable from power supply board to video board, and the 5 
volt supply measured at 5 volts. Used a 20 ohm resistor to create a 1/4 
amp load, still had 5 volts, changed to 10 ohm resistor for 1/2 amp 
load, and the 5 volt was back to a couple of tenths volts. I'm assuming 
that some regulator chip is shutting down due to over current, but am at 
a loss where to go from here.

Some of the components are:
LG monitor model LT953LS
LG power supply board   E74MQ363049011235
    Transformer   LITAI   PT-007921, TF-2820, 2650C0167, appears to be 
an OEM custom  **
    Power Mosfet    (2) 4511GD  PCB is heat discolored slightly in this 
area, 8 PIN dIP
    Voltage regulator ??  AUK647, T0-220 **
    ??      BRF1015CCT, LTGTDIP, T0-220 **
LG video board   75E04862
    1.8 volt regulator for video chip, AZ1086S-1.8EI
   

** Could use info on these parts

Several questions:
1: Is the current to the video board excessive, or is the power supply 
defective?
2: Where do I go from here?
3: Source of parts?

Monitors like this are getting cheaper, and may not be worth while 
fixing, if I can make it work for $25 that's OK, otherwise, our county 
has electronic scrap recycling.

Thanking in advance. :)

These
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