Philips 37PF7321D/37 ,LCD TV, Repaired

Well I figured I would get the posting started by posting a case history.

Went on this call the other day,

Philips 37PF7321D/37 LCD TV

TV would not power on and standby light would flicker randomly. When I have a flickering standby light(random, obviously not an error code) I usually suspect bad electrolytic capacitors on the secondary side on the standby power circuit. In this TV the standby power circuit is on a seperate board than the SMPS board. The board is the standby power and also the audio board integrated. After checking all the electrolytic capacitors on the secondary side of the standby power circuit I found C2510, 2200uF @10V and C2512 1000uF @25V had significantly high ESR. I replaced the capacitors and after putting the audio/standby power board back into the TV and plugging the TV in, the standby light came on solid and when I pressed the power button the TV turned on and fuctioned normally. Another LCD TV with bad electrolytic capacitors. I truly do love at least a few shorted semiconductors to keep me on my toes..LOL...I think we will all still be replacing quite a few capacitors in the days to come. By the way the capacitors in this set showed no physical signs of failure, so if you are still checking for bad caps by looking for the puffy or vented ones, do yourself a favor and get an ESR meter and when you do, use it...LOL

you have to use the esr meter...sometimes if you pull the cap you can see black sticky stuff on the bottom then it's bad. but sometimes they look ok so you have to check them.

Yes an ESR meter is a must for any electronics repair technician. Most electrolytic capacitors show no physical signs of failure, also many electrolytic capacitors will have a measured capacitance value that is still within tolerance even though the ESR has risen to a point that is causing circuit failure so a capacitance meter will often not be useful in identifying bad electrolytic capacitors as well.