I'm trying to fix this laptop screen
Basically the owner is a computer shop and they brought it to me with two screens. They said the repair shop they use could not fix it, so I thought i would try to see if I am better than their current repairer!
OK so I have the original screen which works but has lines across the bottom quarter of the screen
I have the replacement screen, which they fitted and it worked. They then put the laptop on one side for a couple of weeks until they found a buyer. When they showed it to the buyer, the screen would not work - backlights OK but no image. An external VGA monitor works fine
So I thought I would try to fix the screen with no image. I checked the voltages on all the test points on the TCON PCB. They are the same, or very close, on both screens
I then booted into windows with the internal screen attached, using the external monitor as a second display. in both cases Windows knows the screen is there.
So basically I can't see any difference between the the one with lines on the display and the one with no display.
I identified the main chips (Backlight PSU, Gamma, Image?, and a couple of eeproms - see pics. I could only find datasheets for the EEPOMS.
I was thinking maybe the screen with no image would also not detect - but that is not the case. What do the EEproms do? Are they like a BIOS chip on a GPU for example? I'm now thinking of swapping the chip that I think handles the graphics (The parade Wise View chip) and maybe the EEproms to see if I can get the blank screen to work
In fairness I don't have as much knowledge as I would like -
Apart from the obvious voltage, PWM and BL_ON signals on the LVDS, there are also signals called DPRX_AUXN, DPRX_AUXP, DPRXOP and DPRXON. Any idea what these are? Is there a standard pin-out for LVDS or tutorial?
What do the EEPROMS do? Is the data unique to each model of screen (like a motherboard BIOS) or unique to each individual screen (like a HDD eprom)?
Any suggestions of anything else I could check, or should I just start swapping parts over?
Here are two videos (unlisted so you need these links to view) if you would to see what I have tried so far:
part 1 - https://youtu.be/dk3crSH8uo0
part 2 - https://youtu.be/pm-8aTGbKj0
Attached Files
