Before I bought it, I plugged it in and it powered up with an image on the screen, so I figured it was good to go. I remembered I had a different Sceptre monitor a number of years ago that also died. That should have been my first clue. But lucky for me, there's the internet and I found that the most common problem with these monitors is that the capacitors on the power supply board go bad.
This Sceptre X20G-NagaIII has the same AIVP-0017 power supply board as the infamous Gateway monitors. But this one is rev. E and has a different connector on the side. I found the Gateway rev power supply for sale on ebay for $30, but I've had bad luck un-soldering large connectors, so I figured I'd try repairing it instead of replacing it.
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| AIVP-0017 after replacing capacitors and removing connectors |
So I started doing a visual inspection and didn't see any bulging capacitors. There was a spot on the 12 volt LDO regulator, but it was still functioning. The 12 V and 5 V outputs were fine. So I unsoldered five of the 470 uF capacitors so that I could test them.
Original capacitors:
Brand: SAMXON
Value: 470 uF
Vmax: 25
Tmax: 105 C
My multimeter only measures up to 40 uF, so I just checked for shorts and opens and found no shorts and no opens on any of the five. So I brought them to work and tested them on the HP 4284A LCR meter that I had in my lab. All five had capacitance values between 130 and 170 uF. But I'm not sure if those were good readings.
I ordered some replacement capacitors from Mouser.com and replaced all the 470 uF and the two large 68 uF power supply capacitors. It still had the same problem.
I bet the engineers who designed this power supply are still upset about the poor reliability. Where I work, we make sure that the MOSFETs we sell will have no more than 5 ppm fail after 10 years at the maximum rated gate voltage, near the maximum rated temperature. So, to have a capacitor have the life of a light bulb is totally unacceptable to me.
Since I didn't have a circuit diagram, I decided to give up and order a replacement board. As my luck would have it, the board I got didn't match the picture. The picture was of my board, but the one they sent me was for a Gateway monitor.
I unsoldered the connectors and soldered them on the replacement board. I noticed that my replacement board had some capacitors replaced. They didn't match the originals. It was a "repaired" board. So it was a big disappointment, but not much of a surprise when I turned it on and it had the exact same problem.
Monitor at thrift store $25
Capacitors $15
Replacement board $40
Realizing that some deals are too good to be true . . . priceless.
I may spend a little more time on this project later. If I find the fault, I'll update this post.
I have a 3 Gateway FPD2185W monitor setup. These monitors use the same AIVP-0017 PSB and I've replaced the capacitors on all three. But the third monitor has the problem of going black (blue LED still on) after a few minutes. I bought two AIVP-0017 boards from Ali-Express and have had no luck getting them to work any better--even after replacing all of the capacitors. One was DOA. So, I must be missing something. (and yes, I changed the three caps on the logic board as well.) If you have any luck with your board, please let me know what you did, because it is driving me crazy.
ReplyDeleteP.S. It should be noted that if turn off the monitor, wait for a while, then turn back on several times it tends to stay on for a good while--until the screen saver or sleep mode comes on, then it shuts down again after a short while and I have to start whole process all over again.
AIVP-0017 😆 I bought my Gateway in 2005 and it was a demo. It just died. I found almost all of the 470mf caps to be bad. There is a diode though that looks like it burned up so bad I cannot see value of it. Its the one mounted vertically with standoff. You would not happen to have a pic showing numbers/type would you ?
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