MacBook Pro A2251 820-01949-A stuck on 5V

[mferna14]

Hi Dear friend., I am working MacBook Pro A2251 Logic board 820-01949-A. The history was that there was slight liquid on the LHS CD3217 & was not powering on at all. No 20v or any amps. I replaced with known good CD3217s & then got the power but its stuck on 5V .18amp. I did power measurements which are below:
PPBUS_G3H=12v
PP3V3_G3H=3.3v
PP3V3_UPC_X_LDO=3.3v
PPDCIN_G3H=5v ????
PP1V8_SLPS2R=1.8v
Do you think the other RHS CD3217 have to be replaced to as they might have gone defective????

[mon2]

https://logi.wiki/index.php/CD3215_Bootup_Sequence

[mferna14]

Thanks mon2., the Boot seq' is out dated & for A1706... The "Name of Net" does not match in this model schematics. Now I have to figure out all the rails which has to be present before I get the 20V. Do they have any latest boot sequence for CD3217B12???

[mon2]

https://logi.wiki/index.php/CD3217_a...er_on_Sequence

[mferna14]

actually I was checking on Logi Wiki & found it later. I will check all the rails in sequence tomorrow. PPDCIN_G3H=5v should be 20v, there is no shorts & checking YT videos I actually figured out all voltages that should be present on these chips, this is why I was asking should I go ahead & replace the remaining two CD32s. Now before this I will check the CD3217 power seq' first. Thank you very much dear...

[mon2]

PPDCIN_G3H will be 5v as a power on default with all PD power supplies. Only after the PD controller (CD321x ACE devices) are working properly will the higher voltage be selected and then PPDCIN_G3H = 20v. That is, the ISL controller onboard (buck boost type) will be in boost mode when the input voltage (PPDCIN_G3H) is 5v; will be in buck mode when the input voltage (PPDCIN_G3H) is at 20v.

The suspects are still the CD321x PD controllers for now. Test each like the original article by piernov and others. Test the CCx lines in diode mode to confirm they are not defective. The CCx lines are used for the 1-wire BMC communication to exchange the PD contracts by the PD power supply and then the CD321x will select the optimum contract to power the board. By default, 5 volts is the PD contract.

[mferna14]

mon2., after a long trouble shooting, one of the CD3217B12 was defective. Now I get 12V on Fuse F7000, 3.3V on L7660 & 5V on L7030 without any volts fluctuating but still it stuck on 5v .19amp. I checked for any short but none. But only on ONE USB-C connector, all the about required voltages are present & then it resets (Blank on the amp meter) & then back again, other 3 USB-C Ports all are perfect, no reset at all. Kindly help me what is the next step I should look for???

[Stephen]

Did you replace the USBC CD3217 with a new one or a donor?

[mferna14]

Did you replace the USBC CD3217 with a new one or a donor?

Stephen, One side Brand New where it resets always & the other side where the amp volts are stable & taking .19amp both taken for a good working donor board (re-balled both & then soldered to the logic board). Why are you determining that the Brand New ones are not compatible???

[mon2]

The PD controllers are still suspects.

https://repair.wiki/w/MacBook_Pro_A2...cycling_repair

[Stephen]

Stephen, One side Brand New where it resets always & the other side where the amp volts are stable & taking .19amp both taken for a good working donor board (re-balled both & then soldered to the logic board). Why are you determining that the Brand New ones are not compatible???

A2251 must use the chip from a Donor board. You cannot just replace it with a new chip, depending on the side of the chip, you will need the CD3217 from a Donor A2251 board on the exact location. You may have ruined the board moving forward with a new chip. This particular board needs a DONOR, or you can program the new CD3217 chip based on the location. There is a CD3217 chip reader and programmer for this particular reason.

[mon2]

There is a CD3217 chip reader and programmer for this particular reason.

Where? Can you link it? Is it open sourced?

[mferna14]

[QUOTE=Stephen;n3506032]

A2251 must use the chip from a Donor board. You cannot just replace it with a new chip, depending on the side of the chip, you will need the CD3217 from a Donor A2251 board on the exact location. You may have ruined the board moving forward with a new chip. This particular board needs a DONOR, or you can program the new CD3217 chip based on the location. There is a CD3217 chip reader and programmer for this particular reason.[/QUOT

Dear, now I used all CD3217 chips from Donor boards. The problem was still the same, one side was stuck on 5v .19amps on both ports & the other side on one port it was resetting after been stuck on 5v .19amp & the other port (Same side) just stuck on 5v 0amp..... But during all this operation I was surely getting 12v, 5v & 3.3v when the ports on one side were showed 5v .19amp on the amp meter. So I removed the 12v fuse & every single port got stable. All ports were showing Stable 5v 0amp without any kind of resets. I think the problem is after the fuse. CD3217 seem to be working & now I have to trouble shoot the problem after the fuse. & BTW never heard of a CDs Programmer & does these chips need programming???? Are CD3217B12 Progammable????

[Stephen]

https://www.aliexpress.us/item/32568...2usa4itemAdapt

You need this tool for the USB C chips. There is a YouTube video on how to do this. I cannot remember the link but this is the tool that needs to be used.

[mon2]

That tool is just a low cost hardware that provides a USB to SPI bridge based on the WCH controllers. Any flash programming tool can perform the same. This tool is providing a bank of ROM dumps that could be used to reflash the target memory chips.

[piernov]

I do agree with mon2 . Additionally, I'm pretty sure the related SPI ROM dumps have already been posted before.
This does not look like a tool that can deal with the (supposedly) OTP ROM of the CD3217 ICs which causes so many issues with 4-ports boards.

[mferna14]

Read all., so what's the solution??? Means that I only have to reprogram the U3060 & UB260 according & where are the dumps to program these chips again & hopefully can be re-programmed on a Univeral Programmer???

[mon2]

https://www.badcaps.net/forum/troubl...iles-requested

[mferna14]

mon2., thank you very much, got all the bins. Now please inform me one thing., should I just put in all 4 new CD3217B12 on this MacBook Pro A2251 Logic board 820-01949-A & program U3060 & UB260??? & I read that a univeral programmer can be used to program these chips & what ID should I use for these chips or it will automatically detect the identity of the chips by itself?? Thanks dear

[mon2]

Personally cringe and my family jewels run for the hills if dealing with any BGA rework so suggest to leave the CD3217 controllers alone at this time. Although, yesterday managed to rework a 1.4*1.4mm FPGA with 16 balls (WLCSP package) to remove a few shorts. Worked out fine. It is the world's smallest FPGA device = Lattice ICE40UL1K (physically). It is a new product we designed for DIY developers.



Yes, the referenced FLASH devices are correct and believe the downloaded dumps should offer the binaries for these targets. Suggest to make a backup of the original devices using your tools. Be sure your programmer can support the target voltage of 3v3 for the flash.

The part # is in the schematic = W25Q80DVUXIE = Winbond. Ideally your programming tool will support Winbond -> search for W25Q80. Based on the schematic labels, the flash device is operating in standard SPI mode (not QSPI = Quad SPI mode).

Summary - test only the external flash dumps.