original complaint was he snapped the HDMI 1 port from the board while pulling a cable and it was running at the time .. it partially powers on but no image on the screen
.. service manual was difficult to find
-- LG 60PN5000 PU31A.pdf
.. found schematic on http://televid-sib.ru/index.php?topic=19419.0
(shout out to the Russian and Ukranian electronics guys)
.. put back HDMI port after microsoldering .. be extremely careful tons of tiny microresistors and smd caps near the port .. luckily all the pads were still in good condition and not torn but TV is still not turning on .. see the red power light but nothing else
.. found burnt mosfet on main board q604 blown at p600 connector
.. in manual q604 controls the 5v rail to most of the mainboard chips .. checked drain and source to ground and no low resistance to ground was apparent .. do not have this chip and it looked to just be a switch
.. my theory is he shorted the 5v rail when he broke the HDMI output and it burnt this mosfet first sparing everything else
.. the circuit does not look like a regulator just a mosfet switch so I bypassed and soldered S to D pad .. Q604 feeds 5v stby to 5v and now tv is running
.. burn in for one evening .. worked for 5 hours so it works .. will need to be operated with power strip since there is no longer a standby
.. would have swapped in new chip but owner does not want to pay extra for Mouser Digikey this is an older set etc
http://imgur.com/a/snmynOb
.. service manual was difficult to find
-- LG 60PN5000 PU31A.pdf
.. found schematic on http://televid-sib.ru/index.php?topic=19419.0
(shout out to the Russian and Ukranian electronics guys)
.. put back HDMI port after microsoldering .. be extremely careful tons of tiny microresistors and smd caps near the port .. luckily all the pads were still in good condition and not torn but TV is still not turning on .. see the red power light but nothing else
.. found burnt mosfet on main board q604 blown at p600 connector
.. in manual q604 controls the 5v rail to most of the mainboard chips .. checked drain and source to ground and no low resistance to ground was apparent .. do not have this chip and it looked to just be a switch
.. my theory is he shorted the 5v rail when he broke the HDMI output and it burnt this mosfet first sparing everything else
.. the circuit does not look like a regulator just a mosfet switch so I bypassed and soldered S to D pad .. Q604 feeds 5v stby to 5v and now tv is running
.. burn in for one evening .. worked for 5 hours so it works .. will need to be operated with power strip since there is no longer a standby
.. would have swapped in new chip but owner does not want to pay extra for Mouser Digikey this is an older set etc
http://imgur.com/a/snmynOb