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Re: XPS13 all rails present, continuous shutoff cycle
So everything till 1.05V is up and running. The PCH should do its job from here, but it obviously doesn't. Question is ofc, why.
What resistance to GROUND do you measure at the coils which shows voltage?Comment
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Re: XPS13 all rails present, continuous shutoff cycle
PL601 is most likely the ram coil and its not having any voltage. Check the PWM for S3/S5/Ton pins. When you turn on,do you get any voltage there?? What about the 1.8V/2.5V rail?? Are they coming up?Comment
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Re: XPS13 all rails present, continuous shutoff cycle
I suppose I'll need an oscilloscope to check PWM? Also I don't know where to measure those. Lastly, I don't know where to measure for the 1.8V and 2.5V.
I realize this is really far beyond my experience level, but I'm learning, and I thank all of you.Comment
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Re: XPS13 all rails present, continuous shutoff cycle
mEASURE VOLTAGE ON PIN 1/2/10/14 OF PU600.
1.8V can be measured at Pin1 of PU800 or on PL801 coil itself.
I think 2.5V rail is not used here.
All these voltage has to be measured after turning on the mb.
You need needle sharp probes to measure them.Be careful not to accidentally short between pins.
PS: Oscilloscope is a better option but we can get an idea with multimeter as well.Comment
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Re: XPS13 all rails present, continuous shutoff cycle
Pin14 Voltage must be stable. I've not gone through the datasheet of this IC but usually VCC is 3V or 5V. What is the exact resistance on pin14??(no power attached). Is there continuity between PC606 & PC607(pin1 of both caps)?? You dont have the enables for this ram regulator-so cant expect any output.
AS per your measurement, you have missing RUN_ON_P as well as SUS_ON_P.Do you have RUN_ON_EC?Comment
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Re: XPS13 all rails present, continuous shutoff cycle
This mb SIO is in BGA form-so cant troubleshoot much. I've not much to suggest further. maybe other experts here can help.Comment
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Hello everyone,
This is my first post on the forum
I recently purchased a MacBook A2141 from a colleague at work, which had issues with the dedicated GPU. The system occasionally displayed artifacts on the screen and sometimes experienced kernel panics related to the GPU. Interestingly, applying pressure to the VRAM module would temporarily resolve the artifact issues, which made me optimistic about the ease of repair.
Board: 020-01700, Config: Intel i7, 512GB SSD, 16GB Ram.
Before completing the purchase, we decided to erase... -
I am looking at an A2337 and found this for the order of power rails and what they do. Can this be confirmed before I dive into hunting down power rails that do not exist or are not neccisary?
- PPBUS_G3H (12.6V-12.8V)
- This is the main power rail that supplies power to the entire system. Check this rail first, as it must be present for other power rails to work.
- PP3V42_G3H (3.42V)
- This power rail is derived from PPBUS_G3H and is used to power the SMC (System Management Controller) and other essential circuits. It should be present if PPBUS_G3H is working correctly.
- PPVRTC_G3H (3.3V)
- This
- PPBUS_G3H (12.6V-12.8V)
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board came in cleaned up from a previous technician.. after examining the board visually I've seen some work done on the EFI/firmware..
I've taken the chip out and it reads ok on Mac EFI Toolkit, I can read the SN and other information normally..
I have taken a look into the board and I could not find anything suspecting.. I tried to look for corroded chips or corroded caps even to see if there's any areas damaged by liquid and I could not..
I've taken some measurements:
PPBUS 12.6
PP5V_S5 present
PP3v3_S5 present
S4 rails when... -
Bought myself a project thing. Apple MBP16" A2141 820-01700
No shorts, no visible waterdamage.
Dead. no history.
All USBC ports do 20V and charging battery.
If you plug battery/charger PPBUS is 12.6v and all power rails like RTC, 3v3, 5v etc are present. U7800 PMIC all voltages are present APART from PPVCCPRIMCORE_PRIM_REG (not sure if it has to be present at this stage?! resistance is 40 Ohm). SSD 2.5, 0.9, 1.8 are present on both wings. Charger meter shows 30ma or something like this on charged battery.
But what PMIC does is that it power cycles(dropping to... -
Good day! I'm trying to troubleshoot an nm-b242 board. The laptop powers on by default when ac is plugged in. The power button responds and I can turn the laptop off/on, but no display or fan spin. Main rails are present (5valw, 3valw, 1.8valw, vccst, 2.5v_ddr, etc ), even with the laptop turned on. LCD backlight circuit seems ok. The laptop previously had a dead pmic (pu500), which has been replaced and also added pu701 to compensate for the part difference. I'm maybe leaning towards a corrupt bios but I'm not to sure. I'll also add that the fan spins for a seconds then stops. Why could that...
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