Re: iMAC G5 Power Supply API4PC46-290 REV.A pin 8 no voltage
Ok Anyway so is this the PFC MOSFET that is not turned on or could be bad?
Ok Anyway so is this the PFC MOSFET that is not turned on or could be bad?
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Re: iMAC G5 Power Supply API4PC46-290 REV.A pin 8 no voltage
No. PFC is only on when the supply is on, not in standby.
There is no "PFC MOSFET" per se. Just the main switchers.
You are showing output voltages in standby. You should not.veritas odium paritComment
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Re: iMAC G5 Power Supply API4PC46-290 REV.A pin 8 no voltage
Final determination was a wrong type of transistor was used in Q1. The SMD codes can be deceiving at times and so was the case here. A w1P is different from a W1p .
Replaced Q1 with the correct version and the supply returned to proper operation. OP reports that he replaced the Q1 in the others that had the same issue and they are all back to normal.
-Case Closed-
Toastveritas odium paritComment
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Re: iMAC G5 Power Supply API4PC46-290 REV.A pin 8 no voltage
Toasty,
Thanks again for all of your help.Comment
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Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
I have wanting to do this project for quite sometime now and I finally found a switching power supply that will work on this desoldering gun station ZD-915 that the original switching power supply took a shit and just was not worth trying to fix it because this switching power is not quite big enough to handle the heater element and the vacuum pump
One note when I tested the switching power supply and the voltage control board I noticed that this desoldering gun heat up much faster than the original switching power supply which I was really surprised by to the point that I might buy... -
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I once tried to get a ZD-915 desoldering station to work on a 18 volt battery power supply but unfortunately things did not go well but I did find a work around but I might try this idea again but going at a little differently more about this another time... -
Hi all, I just need to know that, can i use SMPS type power supply to test and short circuit detection on a laptop motherboard?
I saw 95% of repair guys are using only Linear bench power supply. linear bench power supply is pricy, thats why i planned to get one SMPS supply.
i know that in linear power supply the noise will be very low comparing to SMPS supply.... -
The sub developed a constant popping every couple seconds from woofer and power LED flickering with nothing but wall AC connected. Connecting an audio cable didn't change anything. It doesn't play but a second or two of audio in between the pops.
Opened it up and discovered the power supply is making a faint clicking or ticking sound.
I measured the amp's output to the woofer and it pulses up to 50mv DC to be driver. The pulses coincide with the power supply ticking/clicking.
I measured the power supply output going to the amp board and it too has this pulsing. Voltage cycles...
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