I have been trying to fix a Philips/LG 170B4 BB/02 monitor and I need your help. Initially, it just wouldn't stay on with the power light off. I took it apart and changed all the electrolytic caps (some were bulging and some were leaking). Now when I turn on the monitor it flashes the display for a split second before going black. The power light now stays on now.
I found a circuit diagram on the internet but although it's mostly the same, some areas are different. The circuit diagram shows three voltages 3.3, 5 and 12v but on measuring, my monitor only seems to have two (3.8v and 12.7v). Should the 3.8v on my monitor be 5v? There are some markings on the circuit board where components should be but there are none so there has obviously been a design change.
If I hold the screen up to a bright light, I can see the image on the screen so the lcd circuitry seems to be working. I bought a backlight tester and all the back lights light up to the same degree (there are 4). The two output transformers for the four backlights have equal resistance on the primary and secondary coils. There is 12v power at various places on the backlight circuitry.
What should I check next?
Also, how do I attach a pdf to this message. I can't see a way.
I found a circuit diagram on the internet but although it's mostly the same, some areas are different. The circuit diagram shows three voltages 3.3, 5 and 12v but on measuring, my monitor only seems to have two (3.8v and 12.7v). Should the 3.8v on my monitor be 5v? There are some markings on the circuit board where components should be but there are none so there has obviously been a design change.
If I hold the screen up to a bright light, I can see the image on the screen so the lcd circuitry seems to be working. I bought a backlight tester and all the back lights light up to the same degree (there are 4). The two output transformers for the four backlights have equal resistance on the primary and secondary coils. There is 12v power at various places on the backlight circuitry.
What should I check next?
Also, how do I attach a pdf to this message. I can't see a way.
But today, I’m making an exception here. Why? No idea. Perhaps only because the repair details are still “fresh” in my head… which is ironic, given this is a 16 year old monitor that hardly anyone will care about today. It is new to me, though. 
I picked it up last November from someone on my local Craigslist. It wasn’t very close to where I live, but was close to a family friend that I had to go visit anyways. So after watching the posting on Craigslist for a few weeks and seeing it getting...
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