MacBook Pro 15" 2017 A1707 Touchbar No power

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

thanks for the update. so you think that CD3215 is borked? I have CD3215C007... does it matter if they are the same or can it be any?
I'm based in Sweden currently, I usually use eBay or AliExpress, unfortunately very slow, still waiting for a voltage chip since weeks for a Lenovo too.

I actually also got me that analyser because you suggested it, but it's also 'underway' .
I'll update when I got news.

This video was very helpful:
https://www.youtube.com/watch?v=6fEQ...ature=emb_logo
it seems Piernov has done a lot of the work to get the logic schemes that they show there. Really nice.
I hope I'll be able to get the chip on and off, any tips? 400 Celcius? need to reball?

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Wait for the proper replacement part. The logic board has to properly communicate over the I2C bus to each working CD3215.

You can source the CD3215 from AliExpress or locally from mobilesentrix.ca - they ship from Canada and also the US at very competitive rates to China.

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi,

Thanks, I'm looking forward to your updates .
I also got some time and looked at the video at logi.wiki.
Based on that I started from 5V on FB200 - then to PP3V3 rail for that source:
based on https://logi.wiki/index.php/CD3215_Bootup_Sequence
on this board it is PP3V3_UPC_TA_LDO - I only measure 1.5 V there.

Then as suggested in the video I measured the voltage on CB308 pin 1 and I get 1.5 V so I think this means the UB300 CD3215 is faulty?

I have to order the chip and try to replace it, or shall I inject 3.3V on the test point and see how far it goes?
I'm also awaiting the USB power meter for on the charger, once I have stuff in I can continue.

Thanks for the support and love to hear some feedback on the above. And thanks to Chris and Piernov for supplying all this information. Great community!

[Stephen]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Sorry Just got back to this thread lol I have so many boards that I put this one to the side. I will be jumping on this board most likely this week.

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Posting the link again for the boot sequence of the logic board to enable the 20V rail:

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

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi. Do not work on this or any repair when tired. The issues will just compound and will turn into a larger mess. Been there, done that and have a case that is similar. Still on our workload to fix. I have lost sleep over this cursed A1706 in the shop - we are determined to fix it. These days we can usually diagnose and repair a board in an hour or so but there are some really tough ones.

When relaxed, can you try the following?

Place the 0 ohm resistor back for now.

1) remove all power to your board

2) place your meter in DIODE mode

3) Red probe (yes RED probe) to any ground shield

4) Black probe onto the CC1 line of one of the CD3215 devices. What is the reading?

5) Repeat with black probe on the CC2 line of the same CD3215 device. What is the reading?

6) Now move to the next CD3215 device and post the DIODE readings for CC1 and CC2 lines on this CD3215 device.

Just remember, no power to the board when you are performing these DIODE readings with your meter.

This logic board works with USB PD (power delivery). The power delivery hand shake is a fancy way of the CD3215 PD controller chatting with the outside PD capable power adapter. The CC1 & CC2 lines are used for this communication using BMC scheme. Only if the CC1 & CC2 lines are operating correctly, then the external power adapter will send back a packet of data when requested which announces 'I am a power adapter and can offer the follow contracts of volts & amps including xx Volts @ yy A, etc.'

For example,

5V @ 2A
9V @ 3A
12V @ 3A
20V @ 3A = 60W adapter with PD support

(not actually sure of the contract values but are similar in format)

This table of contracts are then read into the logic board and the CD3215 will then select, 'I will take 20V @ 3A, etc.' from you - please enable this rail.

The diode readings may reveal that one or both of the CD3215 have CC1/CC2 port pins are defective which may explain why the voltage rail remains static @ 5v. The 5v is a default power on voltage rail.

Unless both CD3215 devices are functioning, the logic board will not invoke the 20V rail (which is actually from your external power adapter) using the power delivery handshake.

The link shared by @Piernov earlier on is an excellent webpage to review the multiple steps taken by the boot process before the 20V appears on your board.

Please post your diode readings when you can.

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

ah, I read about the flexgate, yeah changing the cable, that sucks and it's not cheap too.
I think I don't have that issue, the display was replaced a few years back under warranty.
It has liquid damage and before it went bunkers as now, it just had no backlight, then no screen, then no 20V and now it's as is.

I tried to measure the mosfet, but found myself irritated and out of energy.
Should that 0 Ohm resistor go back or is there a straigh forward way to find the short?

I don't have a microscope and it becomes cumbersome to work in this board.
I'm gonna try and find the energy to try again this week. Problem is I'm just starting and everytime I get into it I have to sleep and some point and then I lose the flow.

Thanks for all the help and tips are still welcome, I'm hoping to get some steps to get through this, I can't imagine major parts are faulty. just lacking experience on how to find shorts and such...
cheers

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Find the side that does receive the power in from your adapter. Confirm it is present on the fuse and continue to trace it to the mosfet (it acts like a solid state, not moving, relay). Then check that the mosfet has the same voltage on the source pin (input) and also on the drain (output).

Post your results.

My a1707 is 99% related to a design flaw with Apple. Called flexgate. The flex cable breaks over use of open / close the lid. Need to either replace the display assembly ($$$$$$) or repair the backlight cable. Will attempt this on Monday.

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Confirm that F3000 is receiving the +5volts.

Then confirm that Q3100 is turning on and producing this voltage onto the PPDCIN_G3H @ +5 volts.

Here is an excellent webpage that discusses about the CD3215 controllers and how they operate.

The SMC (power controller management chip) pings each CD3215 and negotiates the escalation of the power delivery to 20V once all is well.

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

hi, thanks. current problem is F3000 does not get 5V. could feed it with a power supply to test? will research further tonight and update, thanks.
How is your board coming along ?

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Confirm that F3000 is receiving the +5volts.

Then confirm that Q3100 is turning on and producing this voltage onto the PPDCIN_G3H @ +5 volts.

Here is an excellent webpage that discusses about the CD3215 controllers and how they operate.

The SMC (power controller management chip) pings each CD3215 and negotiates the escalation of the power delivery to 20V once all is well.

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

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

P.S. I measured the fuses, they are good, so I got the same readings on both sides

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi, I have the 820-00281-A.
Yeah seems a lot of those go bunkers .

The boardview and schematics I use are attached.

I was actually using the other side of the board, so FB200, that's where in the beginning I had 20V and now only 5.1 (because of one of the USB chips I understand).

I connected the power connector on the F3000/F3001 side, readings:
- F3000 - 0V
- F3001 - 5V

When I connect power on the FB201 side I get 5V on that and nothing on the other side.

Does that mean an issue with the 5V rail ?

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

There are 2 surface mount fuses on the A1707 (assuming you have the 820-00928 logic board - have the same one in the shop now).

F3000

and

F3001

Please see attached and check the voltage on each leg of this 2 legged part.

Do this very carefully as you will need to plug in your external adapter onto the USB connections.

Do you see any voltage on this fuse? Post your results.

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

@openminded - on your circuit board will be an etched number like 820-xxxx format.

Would you please share those details so I can retrieve the exact schematic?

Personally working on a 820-00928 that was brought in to our shop in the last hour. It is the day of the cursed A1707 models

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi, thank you for all the explaning, that helps a lot for a beginner like me .
The WD-40 I will keep aside, it's mostly to get rid of fluid. I'm in Sweden now so can't buy alcohol like that so I am careful with what I have .

aha, so 0402 is the small stuff, it's small indeed! and the 10015 capacitor too, aha.

I got the resistor off, pin 1 has high resistance, pin two has:
- about 153 Ohm with power on
- about 2 Ohm with power off
clear short - but where?

I measured no voltage on pin 1 with power on it - that is when the charger gave 5.1 V - it does not go to 19V (anymore)

The diode measurements (using 1,2,3 as from boardview schematics, 3 being top):

Summary, red probe on pin #1 of the diode (anode #1) and black lead on pin #3. Reading should be about 0.5 to 0.6 volts if ok.
- this reads 0.2 V - black on one , red on 3 gives 2,1V

Repeat with pin #2 and #3.
- black on 2, red on 3 gives 1.99 V , vice versa 0.2V

Setup your meter to voltage mode.

Power up.

Check voltage on pin #1...then pin #3. The readings should be close to each other. Confirm.
- the voltage are 0 on all pins (actually 0.002 on pin 1, power on charge 5.1V)

Power down the board.

Pin #2 is the voltage fed from your battery. Any voltage? If not, battery could be depleted. Pin #3 and pin #2 should be close to each other but only if power is off.

Pin #1 of the diode is powered by your external adapter as the power source and then a local buck (step down) converter.

Post the values for all 3 pins of this dual diode.

- My board is completely out so I have no battery attached. do the values suffice?
I have like 8 Ohm on pin 2 of the diode, with resistor still off all the time. that smells like a short too?

Thanks for the help and happy to learn what a next good stap to make is!

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

To test the diode you have referenced, note that this is dual diode inside a single package. This package is called sot-23 in the industry.

Fancy way of naming this 3 legged device.

The part, when it works correctly, will take in 2 power rails and allow the higher voltage to pass through to pin #3 (common cathode) without impacting the other voltage rail.

The diode does not allow for the voltage on pin #3 to reverse feed into pin #1 or pin #2.

To test this dual diode, remove all power on this logic board.

Set up your meter into diode mode and follow this webpage:

https://www.fluke.com/en-ca/learn/bl...to-test-diodes

Summary, red probe on pin #1 of the diode (anode #1) and black lead on pin #3. Reading should be about 0.5 to 0.6 volts if ok.

Repeat with pin #2 and #3.

Setup your meter to voltage mode.

Power up.

Check voltage on pin #1...then pin #3. The readings should be close to each other. Confirm.

Power down the board.

Pin #2 is the voltage fed from your battery. Any voltage? If not, battery could be depleted. Pin #3 and pin #2 should be close to each other but only if power is off.

Pin #1 of the diode is powered by your external adapter as the power source and then a local buck (step down) converter.

Post the values for all 3 pins of this dual diode.

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi, thanks for the quick reply .

Small addition : I looked at https://www.youtube.com/watch?v=US-Iia5Er7E which was quite helpful.
I might have a short on pin 2 of D6902, so maybe indeed a bad cap.

I don't understand what you mean with all the numbers at the moment, but yeah, things are really small and I am not too well equipped to work with that - magnifying glass, no microscope .
I have hot air / SMD station so I am going to try the removal of the resistor, measure and post the values.

Thanks once again!

[mon2]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

hi @openminded. it is an all age virtual group party. everyone is welcome.

1) lose the wd40 - not sure I would consider that for anything electronic. also concerned about it being flammable around heat sources.

pure alcohol is fine and recommended - ideally sourced from an electronics vendor but should be ok to get medical grade from a pharmacy in a pinch. higher purity is always recommended.

2) proceed with caution - if in doubt - DO NOT power on the board. The A1706/A1707 or newer are very tiny and dainty PCBs. Not sure about you but the parts are quite small and unless you have a microscope, almost impossible to work with once the parts are removed or damaged.

We have a full SMT line in-house and prefer to stay with 0402 parts for our designs. Have worked with 01005 placements just to exercise our machinery but when Apple sprinkles these all over their PCBs, have to believe they want to torture the repair shops.

3) Remove R6923 for now. Be sure that all power is OFF to the logic board. Place your meter in resistance mode. Then black probe of meter to ground on the board (metal shields are good). Red probe onto the pin # 2 of where the R6923 used to be. You are testing to check the resistance to ground for the voltage rail. If the resistance is too low, then there is a shorted cap on this rail and causing the poor, low current regulator to shut off to protect itself.

If it is safe to do so with this logic board, power up and place your meter in voltage mode -> check the voltage on pin #1 of where R6923 used to be.

Is this voltage regulator still working?

Post your values for each requested points of interest.

[openminded]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power

Try check on pin 2 R6923 for shorted.

That is a high reading and that is fine. If you bring back the zero ohm resistor, this line starts to fluctuate or is it steady?

Hi, I hope it's ok to join the thread, I have a very similar problem.
Short background: MacBook Pro 15 late 2016 A1707 820-00281-A board. I have boardview and schematics, it's one of my first repairs.
Cleaned board with toothbrush and WD-40 and some place alcohol.

Before cleaning the backlight seemed broken, but also the non-backlit screen got dimmer - otherwise it chimed and booted and worked with external screen.
After clean: no more chime - fans on - off /on loop it seems.

I read this whole tread and tried measuring.
I had a steady 3.4 V on the 0 Ohm R6923 on both pins, but only after plugging in the USB charger (Apple, 87W) and sometimes for a few seconds, sometimes longer (minutes).
Then it goes to 0 V for a while and if I measure a bit later it is sometimes -0.4 V and then 0.

I don't have a USB amp meter yet, but I had a steady 20.1 V on the fuse shortly after the USB powerplug, so it seems I'm good on the USB chips part?
Actually while writing this I also only have 5V on the fuse that was 19 before, seems things are deteriorating .... but also that I am in the same situation now?

I'm confused about S0 - I understood from reading that 20V means S0 is reached so those should be measured.

but it seems I suddenly have a short on pin 2 of R6923 using a Fluke in bleep mode, it bleeps.. In diode mode about 1.5 Ohm.

How should I proceed now, take of this resistor and measure both points in diode mode?
Thanks, hope I'm not hijacking the thread, thought we might all get to a working end result

[Stephen]

Re: MacBook Pro 15" 2017 A1707 Touchbar No power



This is what I am working with atm. We are still adding more repair equipment to our office.