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Timp74
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Last Activity: 06-16-2024, 11:20 AM
Joined: 04-13-2018
Location: Barcelona
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  • To answer my own questions... I finally had the time to look at this machine again now that the boardview is availble. Turns out the machine wasn't powering on because there was crap under the slave PMIC. Took me a while to work out. I noticed that the 1v8_s2 rail was beening pulled up to 2.1v by 3v8_aon, there was 300 ohms between the rails, it should be Kohms. I guess other rails were off too. Anyway I soaked the board in isoproponol for a few hours and ran a flux cleaner under the slave PMIC. The machine now boots and works fine. I don't see any reason the a missing backlight bucks/boost...
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  • Re: iMac 27" 5K 2017 bios dump needed

    Can I just flash this .bin and it will work, or do I need to clean the ME region or do anything else?
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM

    Okay. So I removed the KB9028g chip and traced the pins. They are different to the pins given in the first post. Maybe a different version of the motherboard. The one I'm working on is version 001 I think. Part of the number is covered by the CPU support bracket so I can't see it clearly. Anyway, these are the absolute pin numbers for programming the KB9028g on this board:

    KS03 - 37 - Connect to gound on MB, which also needs connecting to GND on the programmer.
    KSI4 - 28 - CS
    KSI5 - 27 - CLK
    KSI6 - 26 - MOSI/DI...
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM



    Just to add, the pinout for the KB9028g BGA chip is shown in the schematic for the Stream 14-z010nr which is on Badcaps......
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM



    Where did you get the boardview from? I've never bought anything from the websites that sell these things. Do they actually work?...
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM



    To answer my own question. The PU1 IC which looks like a TPS51225c has 3.3 and 5 volt LDOs which are aways on. It also controls the 3.3 and 5v rails. In the GE66 MS-1541 the circuit looks similar to the MS-16K2....
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM



    Please see the photo. It's not very clear but the pins are connected as you listed them in the first post.

    I'm wondering about the 3.3v.. With out KSO3 connected to ground, when powering up the motherboard a red light flashes and the 3.3v and 5v rails come up for a few milliseconds and then reset. They do that in time with the red light flashing. WITH KSO3 connected to ground both 3.3v and 5v are low. So where does the EC chip get it's supply voltage from in programming mode?...
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  • Re: MSI GE 66 Raider - MS-15411 EC ROM

    Hi, Thanks for sharing this. I have a GE66 10sf that had a blown EC controller. I've replaced the controller and connected a CH341 programmer to the pins as listed in your message. Unfortunately the programmer can't detect the EC controller as an EPROM. Was there a particular order in which you powered things up? When you had to retry the programming what error was it giving for you?

    Would be great to get the boardview and schematics for this laptop if you have them.

    Thanks again for sharing your findings.
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..



    Thanks Yra98621. Did you have any luck with your repairs?

    PMU_VDDHI doesn't seem wildly off, so I'm going to look for other causes..

    I finally got the RAA209100B backlight buck-boost converter from China. Unfortunately after installing it the motherboard still doesn't work. There are some odd voltages on a few pins. Notably, the BL_PWR_EN signal from U8100 the master PMU to the backlight controller only comes up to about 0.5v, and it's not a very sharp transition. I'm wondering...
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..

    Another possibility. R8170 was slightly corroded so PMU_VDDHI may be wrong. When PPBUS_AON is at 12.4 volts PMU_VDDHI is at 2.45 volts. Could anyone confirm this is the right ratio? There are two different options in the schematic, nether would give this ratio.

    Also. The machine can't be loading anything from the EEPROMs as those need PP1V8_AWAKE. This power looping behaviour is probably because of the PMICs. Possibly a sensor out of range, although the majority of those also need PP1V8_AWAKE.. I'm running out...
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..

    I have given in and paid 50 bucks for a single chip from China. Will post update when it arrives and I try and install it.

    I checked all buck and LDO outputs on the master and slave PMICs. All good. The only suspicious thing is that the vpump on the slave PMIC u7700 seems not to come up to 4.9 volts and has different diode/resistance to the master PMIC. This is needed for the switched outputs. So things like PP1v8_AWAKE. I'm assuming this is because it's programmed that way, not because there is a fault on U7700....
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..



    This is very interesting.. Can you add more NAND to change the size of the SSD?...
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  • Re: WLCSP Damage..




    Thanks for your help on this. Much appreciated. I removed the two inductors as suggested, but it doesn't seem like the audio WLCSP chip is the problem on the PP1V8_AWAKE rail. There's no short on it, it just doesn't come up okay. I think I may have damaged the slave PMIC buck controller U7700 while trying to fix the backlight boost controller. It's a mystery how. There is no direct connection between the two chips. I'm still hoping I'll find something else I damaged while installing the motherboard which explains the problem...
    ...
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  • Re: WLCSP Damage..



    I was trying to fix the backlight circuit, but once I had worked on that, the laptop wouldn't power on. After diagnosing the problem, it looks less like it's because of my work on the backlight circuit. So I've been looking at other damage on the board. This is the only chip on the power line that's not working properly that has damage. Although it's not much damage, so that's why I want to know about people's experiences with WLSCP chips....
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..



    I hope you can fix it. I'm assuming the 'POWER ALIASES..' pages of the schematic list the power rails in a similar order to which they come up.. Like the 820-02100 I'm trying to fix has all rails up to PP1V8_AWAKE working(S2 rails are oscillating, but they come up to the correct voltage when high). PP1V8_AWAKE is only coming up to 0.7v and PP1V2_AWAKESW_BLC stays at 0v.

    BTW. Have you successfully replaced NAND chips in Macbooks before? I thought they were factory programed for the machine they...
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  • WLCSP Damage..

    How sensitive are WLCSP packages to damage?

    The photo is of the Audio/Headphone CODEC on a Macbook a2485 820-02100 motherboard. The motherboard doesn't power on, possibly because this chip is holding the PP1V8_AWAKE rail down. It's not shorted, just the 1.8v rail going into it only comes up to about 0.7v, then resets. Which I think is stopping the machine powering up fully. There are a few other chips on the same rail but they all look fine.

    Anyway, if anyone has an opinion on WLCSP chips I would like to hear it. I've used Intel CPUs with chips/scratches in the die...
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..



    Hi, Sounds like you need to work through the power rails again. If it's restarting like in the video, it may not have all _AON rails working.

    Thanks for letting me know your opinion on the 209100B1 chip. Did you try turning your a2442 on when the chip was removed? There is an AliExpress seller that has the chips for 50 dollars. Which is still ridiculous, but if I knew it would fix the motherboard I would buy one....
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..

    So to add. Looks like most AON rails are stable. Most S2 rails are switch on for a fraction of a second about every second.

    PP1V8_AWAKE is weird. It rises up to about 0.7 volts and then resets with the other S2 rails. It's switched from PP1v8_S2 by U7700. PP1V8_AWAKE measures 0.342v in diode mode and more than 250Kohms. It seems to power the audio ICs and some level shifters. Seems completely unrelated to the backlight IC UP800...
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  • Re: 820-02100/02098 LCD Backlight Controller IC UP800..

    Sorry. It's actually drawing about 1 watt at 5v, not 1 amp. I have a new USB DP meter that I should learn to read... It also power cycles after about 25 seconds, not 20.
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  • 820-02100/02098 LCD Backlight Controller IC UP800..

    Hi All.

    Does anyone know if Macbooks will power on without their display backlight controller ICs? Explicitly I have an a2485(very similar to a2442) that has the UP800 IC broken/missing. On attaching a USB PD charger it stays at 5v ~1A for 20 seconds and then resets and repeats the cycle.

    The history is that the machine was water damaged to IC UP800. A Renesas 209100b1 Buck Boost controller. The machine still worked, but without the display backlight coming on. UP800 wasn't generating any switching signals to the four driver mosfets. I removed UP800 and check the...
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