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Equipment Repairs => LCD TV forum => Topic started by: blackmail on April 22, 2010,13:29:13

Title: xenois lcdx32whd88
Post by: blackmail on April 22, 2010,13:29:13

great site lads
I have a xenois lcdx32whd88 the original fault was 24v on the the power supply was not working, repaired that. now the lamp inverter goes out before the lamp triggers.
when I replace the 24v with external power supply the inverter stays on?
this one is stumping me!

Title: Re: xenois lcdx32whd88
Post by: In_Focus on April 22, 2010,14:17:13

Does this set have a 17PW20 PSU? If so check the ‘Backlight ON’ 3.2V supply at PL802 pin 12.
The 3.2V is an enable signal from the CPU to the inverter PCB (via the PSU), to switch on
the backlights. If this is low, the backlights will switch off. Try replacing Q841 BC858B, D861 BAT254, C904 1uF 16V.

Title: Re: xenois lcdx32whd88
Post by: blackmail on April 23, 2010,10:44:32

thanks for the info
3.3v enable pin 12 is present when processor turns on the inverter, when the processor turns on the inverter the blue led lights for about 2-3 seconds then goes out.
if I bypass 24v with external psu, the lamp stays on and everything works ok.
the psu board is a 17pw20

Title: Re: xenois lcdx32whd88
Post by: In_Focus on April 23, 2010,13:55:36

Bit of a chicken and egg situation, you really need to substitute a good PSU to save you a lot of time. Maybe the 24 Volt supply is a smidge low or cannot supply enough current. The blue LED you mention, do you mean the one on the front of the TV or on the inverter? one on the inverter would suggest an LG/Philips panel, their inverters are also not the most reliable.
Good luck.

Title: Re: xenois lcdx32whd88
Post by: WILLYAM1 on April 23, 2010,15:44:28

check 2 capi 12 nf or 15nf/630v usully in blue color or brown.
willyam1

Title: Re: xenois lcdx32whd88
Post by: blackmail on April 24, 2010,08:24:02

that sorted it cheers m8