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Equipment Repairs => LCD TV forum => Topic started by: Turnip on April 05, 2014,09:32:39

Title: Bush IDLCD26TV27HD Stuck in S/by
Post by: Turnip on April 05, 2014,09:32:39

Hello folks,

Have one of these (17PW22-4 and 17MB12-2) where Blue S/by led glows but set remains in S/by. Have a Eeprom feeling but can't find it on the shematic.

Noted IC303 (a plug in 8 pin chip) next to the Proc. but can't find that on the shematic either. Notice TV Tony kindly uploaded the bin a while ago.

Any thoughts - Thanks - Chris.

Title: Re: Bush IDLCD26TV27HD Stuck in S/by
Post by: jordan on April 05, 2014,11:16:19

????

Title: Re: Bush IDLCD26TV27HD Stuck in S/by
Post by: Turnip on April 05, 2014,11:38:36

Thanks Jordan,

Will try sort the Eeprom, but admit have the shematics already, and a nifty dump from a Quuq (but spell checked) hero - Chap doesn't say which chip it is.

Matter of knowing the which chip is the Eeprom so can try sort - Thanks - Chris.

Title: Re: Bush IDLCD26TV27HD Stuck in S/by
Post by: Turnip on April 06, 2014,10:51:32

Hi folks,

Sorted - was looking in the wrong place -  Power supply after all  

Found this file  - No S/by Led – At C836 (1000mF/25V) there should be a voltage of 12V was only 4V.

Solution - Replace R992 (6.2 Ohms) and Q803 (FET MTP6N60E).

(Q803 is the lower fet in the diagram and supplies the 12V to the sub-panel buck converters for 3.3V and 5.0V)

Interesting as my Q803 was marked Y2010DN –  A  dual 100V 20A shottky diode device and not a fet as in shematic and R992 was a 7A SMD fuse - Q803 was  S/C and the 7 Amp fuse had popped.

Other interesting thing - No discharge resistors on the 2 x main caps - Ouch !