Hi friends, working on a MacBook Air A2179 logic board 820-01958-A logic board. It's just stuck on 5V .19amp on one USB-port & then when I use to the other port it's also stuck on 5V .19amp but on this port it resets after few secs & start over with the same said voltage. I assumed that one of the CD3217B12s is defective, & replaced both with known good ICs. The status & result remains the same. I checked for shorts or liquid spill, all clear. On F8400 there is 12v present, but no 5V or 3.3 volts. There are LDO voltages on the both CDs 3.2v & 1.5V. Kindly if someone can help me troubleshoot this. Thanks in advance
-
-
Is the fixed current draw immediate or climbs up to this value? If fixed, often will be a shorted part.
On the missing power rails, test if their output legs are shorted. Test if the local enable pins are present or not. -
Thanks mon2., the current draw is stable to .19amp, does not increase or decrease.I checked for shorts, cannot find anywhere, ever coil & caps have resistence. more than 2K. Enable pins of what?? IC (CD3217B12) you mean??I checked the voltages, only the G3H (20v) is missing. Rest the 12v & LDO voltages are fine & present, only goes when the logic board resets again.Comment
-
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... -
Hi there. I am currently trying to figure out if I am undergoing the sunk cost fallacy.
I’ve bought a very cheap MacBook Pro 14 A2442 off eBay. I did some checking and the symptoms were pointing towards a NAND failure.
After some consideration I got an original logic board from Apple as an replacement. However after installing I have no backlight.
I can see the Apple logo if I point a flashlight at it but the MacBook seems to be going to recovery mode.
anybody have an idea of what’s up here? Is the board dead on arrival or is my screen... -
Apple MacBook Pro 13" A1706 Logic Board 820-00923 Schematic & Board View...
-
I hope this is the right forum to post in despite not technically being a repair, but still a question of swapping boards.
I thought I'd explore the possibility to upgrade an existing working Samsung ue55nu7096u with the logic board (and power board if needed) of a newer model (ue55ru7105k) of the same size and appearance (and resolution). The reason being I'd like the extra inputs of that board including component in, an extra HDMI port and bluetooth. Its panel is broken so I have no use for the board otherwise.
The models launched in 2018 and 2019 respectively.... -
Hi all, I just want to share the repair of my 60PK550-UA TV set.
The TV set was powering on, just no image. After verification, nothing wrong on the YSus or ZSus boards. Nothing wrong on the main board either.
But I noticed that the LED was not flashing on the Logic Control Board. This is an EBR63450301. The LED is supposed to flash even with all the flat cables disconnected, with only the power cable attached.
All the voltages measured at the electrolytic capacitors on the board were good. From top left to bottom right:
C57: 3.30V
C61:...07-20-2023, 12:38 AM
Comment