820-01598 liquid no start

grmacs

Member
I was able to get the board to go to 20V by cleaning up various areas of the board affected by liquid. Replaced C6700 and what I believe is C7234. I don't have a boardview for this and not even sure if this is 01598 or 01958 board for sure as I can't find a F'ing part number anywhere.

It appears I have good voltages according to the power sequence chart I referenced up through P3v3main_Pgood. I am not sure how to find P5VG3S_EN or PCHRTC_RESET_L as they don't seem to correspond to the 01521 boardview.

Board now takes 20V and eventually the wattage and amperage go to zero. If battery is plugged in the board cycles down to 5V and back to 20V every few seconds.

I tried connecting to Configurator2 but the device does not showup on the host machine. I asked customer and believe the target device has Catalina and matched accordingly but I believe it should still see the device at least regardless.

Please help!
 

2informaticos

Administrator
Staff member
The board must go into DFU whith just 5V input voltage through USB-C.
If is not recognized, you have a problem with T2 itself, or missing some AWAKE, or SLPSW2R voltage.

Liquid damage on audio board, or flex, can easy kill T2; some data lines to close to PPBUS_G3H...
 

grmacs

Member
This has minor corrosion around many areas of the board... No shorts that I can determine.

I haven't much experience with these new boards though.

Is it correct that the device should at least appear in configurator 2 simply by having power to it and the cable plugged into the proper USB-C port on left closest to the front?

I'm not sure where to find PP3v3_AWAKE or PP1V2_AWAKE... doesn't match location on 01521 on board. DO you know where it's located on 01958?
 
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2informaticos

Administrator
Staff member
No way to know where exactly check these rails, without real boardview.
If board has many voltages present, it should appear in DFU.
If not, most likely bad T2 chip...
 

grmacs

Member
Yeah. No shorts that I can find and all voltages I had locations for related to t2 are there. I’m thinking there will never have to purchase post t2 donor boards being they die upon sneezing
 

grmacs

Member
I ended up ordering a replacement board that came with Touch ID but when trying to test the TouchID by starting a setup of fingerprint, it immediately gives a failed message. I assume this means that the TOuch ID sent was not a pair for the board but wanted to see if it's possible that, because the battery is bad (waiting for replacement), if there are quirks to these new macs that would not allow things to be setup due to an existing fault somewhere else? I also ordered another audio board wondering if the original has also had enough liquid contact to fail and cause issue with Touch ID. Audio board was affected by the spill but doesn't visibly look like it would've failed.

Your thoughts?
 

2informaticos

Administrator
Staff member
If audio board was affected by liquid, I hope you didn't connect it with the new board.
Leakage from PPBUS_G3H to T2 data lines, is not a good thing...
 

grmacs

Member
Mark this one solved. Replaced the audio board today and that solved the issue of the touch ID not working.
 
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