Hello,
I got this A2141MBP a few month ago. It wasnt able to boot nor display anything. I let it on a shelf.
I plugged my USB-C ampmeter today on each USB-C port. Being in front of the MBP, I got:
USB-C, left* side, back*, 20V and 2.4A. When I pressed on On, or maybe before, I got the "empty battery" symbol displayed on screen
USB-C, left* side, front*, 20V, and 0.13A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
USB-C, right* side, back*, 20V, and 0.5A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
USB-C, right* side, front*, 20V, and 0.5A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
I opened the MBP, and noticed:
- corrosion around pin 4-5 of U4901, pins 1 2 of C4956. (greenish oxyded copper). I carefully cleaned the area
- corrosion around testpad TPB200:1 / TBT_T_SPI_CS_L (blue shade)
- white residues, thought it was dust at first, no picture, between pins 1 of C9001 and C9004, and U9000.
After that, I put back everything in place.
Now, I measure:
- stable 5.15V but cycling 0.15 to 0.48A on USB-C left and right, front.
- cycling 5.15V - 0V / ON/OFF USC-C left and right, back.
Furthermore, if I apply alcool on the U4901, while the MBP is plugged (front USB-C port, stable at 5.15V) on the charger (battery uplugged), nothing happens
But, if I apply alcool on the U9000, the drop of alcool pulses 1x per second. It's like dancing on top of the U9000
While measuring the Voltage on pin 1 of C4956, I ripped it off the board. Will put a new one in place, of 0.1uF. (I measured it when it was soldered on the board but got 50nF anyway)
I notice there is no R4915 on the board, but there is one on the schematics. I don't have any other A2141 logic board to do a visual comparison.
Could someone confirm that they should be a resistance there ? Could it have blow away when the short occured , months ago ?
PPBUS_G3H is at 12.55V (CB702, CB703, CB704)
Needless to say, I don't have my PP3V3_G3H_T. Instead, I have something fluctuating between 1.01 and 2.1V, when measured on pad 1 of C4956 (R4915 and C4956 being gone)
Reball U9000 ?
*front/back, left/right, referencial being the top of the trackpad. Back: closest to the screen. Front, closest to the trackpad.
I got this A2141MBP a few month ago. It wasnt able to boot nor display anything. I let it on a shelf.
I plugged my USB-C ampmeter today on each USB-C port. Being in front of the MBP, I got:
USB-C, left* side, back*, 20V and 2.4A. When I pressed on On, or maybe before, I got the "empty battery" symbol displayed on screen
USB-C, left* side, front*, 20V, and 0.13A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
USB-C, right* side, back*, 20V, and 0.5A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
USB-C, right* side, front*, 20V, and 0.5A cycling up to 1A. No Boot (and nothing displayed on screen regarding the battery)
I opened the MBP, and noticed:
- corrosion around pin 4-5 of U4901, pins 1 2 of C4956. (greenish oxyded copper). I carefully cleaned the area
- corrosion around testpad TPB200:1 / TBT_T_SPI_CS_L (blue shade)
- white residues, thought it was dust at first, no picture, between pins 1 of C9001 and C9004, and U9000.
After that, I put back everything in place.
Now, I measure:
- stable 5.15V but cycling 0.15 to 0.48A on USB-C left and right, front.
- cycling 5.15V - 0V / ON/OFF USC-C left and right, back.
Furthermore, if I apply alcool on the U4901, while the MBP is plugged (front USB-C port, stable at 5.15V) on the charger (battery uplugged), nothing happens
But, if I apply alcool on the U9000, the drop of alcool pulses 1x per second. It's like dancing on top of the U9000
While measuring the Voltage on pin 1 of C4956, I ripped it off the board. Will put a new one in place, of 0.1uF. (I measured it when it was soldered on the board but got 50nF anyway)
I notice there is no R4915 on the board, but there is one on the schematics. I don't have any other A2141 logic board to do a visual comparison.
Could someone confirm that they should be a resistance there ? Could it have blow away when the short occured , months ago ?
PPBUS_G3H is at 12.55V (CB702, CB703, CB704)
Needless to say, I don't have my PP3V3_G3H_T. Instead, I have something fluctuating between 1.01 and 2.1V, when measured on pad 1 of C4956 (R4915 and C4956 being gone)
Reball U9000 ?
*front/back, left/right, referencial being the top of the trackpad. Back: closest to the screen. Front, closest to the trackpad.
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