Sharp lc-60eq10u power issue

[joec9999]

Hi,

I have a Sharp lc-60eq10u with power board DPS-167CP A. The symptom is two slow blinks followed by two fast blinks from the led on the front of the TV.
I looked up the error code in the service manual and see it is related to UR+13V.

I removed the power board and powered it up on the bench by connecting PS_ON to BU5V and was able to power up the board. UR+13V was present measuring about 13V. I also measured the voltage at C7800A/B and found that it started up at about 175 VDC and slowly climbed (took about two minutes) up to 395 VDC.

At this point, I powered down the board and resoldered some questionable connections and put it back into the TV. After reapplying power, the TV showed the 2/2 blink error pattern again (without pressing the power button). I then pressed the power button and the TV powered up and played all day.

I unplugged the TV and let it sit overnight. The next day I plugged it back in and the TV showed the 2/2 blink error again.

The one thing I question is the +395 V across C7800A/B and how it took so long for it to build up while I was testing it on the bench. Could this be the issue?

I'm not absolutely sure this is a power board issue and would like some input on this.

Thanks in advance,

Joe

[dskall]

Re: Sharp lc-60eq10u power issue

I believe you should have your 175vdc at standby, and get your 395vdc almost instantaneously when powered on.

[Andrew F. Ali]

Re: Sharp lc-60eq10u power issue

The e-cap/s C7800A/B is probably bad...It my not show any physical evidence...The capacitance probably decreased over time.