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Equipment Repairs => LCD TV forum => Topic started by: hawkbit on February 24, 2010,11:22:09

Title: LG 19LH 2000 power supply
Post by: hawkbit on February 24, 2010,11:22:09

Hi
Having problems with PSU for this TV - PSU receiving power up voltage from main board but will not complete next sequence. Have the service manual for this unit but schematic for PSU is not included, Any ideas of possible fault or where I can access the PSU schematic.

Would appreciate any help.

Thanks

Derek

Title: Re: LG 19LH 2000 power supply
Post by: Turnip on February 24, 2010,12:01:17

Hi Derek,

On power up, are there any secondary voltages, pulsing or otherwise ? A piccy of the power panel might give us a clue - Chris.

Title: Re: LG 19LH 2000 power supply
Post by: hawkbit on February 24, 2010,14:12:40

Hi Chris

Thanks for responding.
I've attached front & rear pictures of the PS board.
The board produces a steady 5.2 standby volts and a steady 15v (actually 14.7). When powered up I get a pulse of about 3v from the main board onto the "DIM" plug connection of the PS board. I'm assuming this pulse initiates further power supply values to the main board however nothing appears to change. I've also assumed that there is a third stage that follows where the main board initiates the inverter to strike the lamps - lots of assumptions I'm afraid but the cct is particularly difficult to follow off the board tracks.

Regards
Derek