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Equipment Repairs => PLASMA TV forum => Topic started by: call me al on July 20, 2019,08:32:59

Title: lg 42pn450b
Post by: call me al on July 20, 2019,08:32:59

Hi All Have a LG 42PN450B Fault Dead no standby light .There is 5v supply present to main board no other outputs from psu.Am thinking its a main board fault but am not sure .Any help appreciated

Title: Re: lg 42pn450b
Post by: downunder on July 21, 2019,03:35:09

Hi Al, Is that a legit model number? Probably your first move is to ascertain if the main board is sending a PS-ON signal to the PSU to activate it. If not, then its the main board. A conventional roasting of the main board should sort it.               Bruce

Title: Re: lg 42pn450b
Post by: call me al on July 23, 2019,08:08:51

sorry about wrong model its 37ls5600 must be losing my marbles totally anyway have tryed cooking still the same can i fource the psu on i wonder

Title: Re: lg 42pn450b
Post by: downunder on July 24, 2019,03:20:39

Cant see any reason why not. Same thing, though, the PWR-ON pin should be around 3V - is this present? If not, short PWR-ON pin to the 5V pin via 100 ohm resistor. If the PSU is functional, voltages such as 12V, 24V should come up. This does not include the backlights which are likewise activated by an additional resistor to the INV-ON pin.               Bruce