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Equipment Repairs => LCD TV forum => Topic started by: Keith on June 08, 2011,08:24:57

Title: LG 42LF65
Post by: Keith on June 08, 2011,08:24:57

Hi all,

Picture goes after about 15 minutes, back lights are OK, sound OK. I have done the filter mod, but problem is still there! Any ideas?

Thanks

Keith

Title: Re: LG 42LF65
Post by: watteau on June 08, 2011,08:47:16

Hi,
Have you checked the LT supplies when the fault occurs?
I've had problems with the 100ufd capacitors decoupling the outputs from the stabilisers (C970 etc.).
Worth a check.
Regards,
John.

Title: Re: LG 42LF65
Post by: Keith on June 10, 2011,11:35:34

The PSU outputs are clean and good.

The problem was IC901 on SSB 3.3V regulator

Keith

Title: Re: LG 42LF65
Post by: stellaman on June 11, 2011,11:16:10

Keith, what was the component number and where did you source it from? Was it a AZ1085S if so where can I buy one?

Thanks, Dave

Title: Re: LG 42LF65
Post by: Keith on June 12, 2011,04:09:17

Hi Dave

Original part is FAN1587A33,  3v3 3A.

I couldn't find anything similar at 3A in the same package, so fitted a 5A rated slightly larger package with slight mod to get it in! Tested 2 days continuous no problems.
With the fault the output of the reg only dropped by 100mV, but that would appear to be enough to send the processors scatty.

Keith

Title: Re: LG 42LF65
Post by: stellaman on June 12, 2011,07:15:10

Thanks for reply Keith.

Dave