Sorry to hijack this thread, I have the same board with a similar problem. First one of the CD3215's was dead, no voltage on USB meter. Replaced faulty CD3215 and now get 5v climbs quickly to 12v around 200ma then loops back to 5v then loops at 5v most of time. Very low PPBUS ma reading but pp3v3_g3h present. I have replaced ISL and diode which takes battery and PC DIN. It seems there is a short before machine fully boots but struggling what to look at next. Hoping CPU not fried, I have replaced 2 cracked tantalum capacitors which were cracked ( think this was the cause originally ) no water damage, clean board otherwise and no other visual damage under microscope.
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Are you using a suitable power adapter that offers 20V as a power delivery contract? Re: PPBUS - remove the downstream fuse(s) and then power up again. Without the fuse(s) on PPBUS_G3H, is the ISL side (producer) stable? What is the voltage to ground without a load? -
Hi Mon2 sorry I didn't get back to you straight away, I removed R7000 and R7001 and the voltage jumped to 20v! checked again for shorts on the upstream side and nothing, then before I had chance to do anything all 4 CD3215's back to 5v? I have since replaced ISL, D6902 & U6903 and have 2 of the CD3215 kind of cycling and 2 at 0amp draw. Also PM_EN_P3V3_G3H is 5.06v?
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PP3V3_G3H = 4.472v?Comment
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That is a too high of a voltage. Very concerned about damage to the other logic on this 3v3 power rail.
This overshoot of the output voltage is linked to the incorrect feedback resistors (R6910-R6913) on the buck regulator @ U6903. These critical resistors define the final output voltage of 3v3.
While it may be too late, consider to flux and remove R6923. This 0 ohm resistor will stop this high voltage from powering the same devices that are downstream. Then focus on correcting this power rail to become stabilized to 3v3. Do not add R6923 till this rail is @ 3v3.Comment
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Thanks for your response Mon2, I will give that a go and see if the voltage lowersComment
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Hello everyone,
I'm currently diagnosing a MacBook Pro A1707 motherboard that does not power on. I've gathered some data but am stuck and need expert advice.
Note that i'm a beginner in electronics and i'm trying to learn while trying to repair this macbook that my work gave me. I'm really curious and love understanding how thing works and i already learned so much.
Only one usb c port is taking 20v and have 12.5v on PPBUS_G3H. when trying other ports, 2 are not going to 20v and one is going to 20v but the CD3215 is getting really hot.
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As the title states, got one CD3215 chip being a complete butthole to me. All readings on the other 3 chips read as follows
5.16V .47amp
5.16V .47amp
5.16V .47amp
5.16V .04amp (this guy is the issue) (U3200)
So I went ahead and replaced the chip, (actually 3 times with 3 new CD3215 chips) all same issue, at first it wasn't reading at all then it finally started reading. I can rest assured is it not the CD3215 chip now but something else is causing this port to not fully read (god I wish the board would just turn on so we can just recover the data)
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Hi, I'm working on a MSI laptop, Motherboard number MS-16W11, GF-65 Thin 10SDR-459US. Went to another shop because the screen was flickering, but it was working well on an external monitor. The LCD was ordered and the laptop was returned to the customer and it no longer worked. It was then sent to another tech (by the shop who ordered the LCD) and the EC (ENE KB9028Q) was replaced with a donor from another MSI board with different board number and no programming was done. It looks like work was done on PU6 (TPS51225) as well as one of the GPU mosfets was burnt (I removed all three GPU mosfets).... -
Board Model: 820-00923
Issue: Board takes 5V @ 0.694A on all ports. No signs liquid.
Customer stated: Died during an update whilst battery was at 10%. Tried plugging in but it died.
Board takes 5V at 0.06A on all USB-C ports..
Board is clean with no visible corrosion or liquid damage.
PP1V8_UPC_TA_LDOA - 1.8V
PP3V3_UPC_TA_LDO - 3.32V
PP1V8_UPC_TA_LDOD - 1.8V
PP1V1_UPC_TA_LDO_BMC - 0V
PP1V8_UPC_TB_LDOA - 1.8V
PP1V1_UPC_TB_LDO_BMC - 0V
PP1V8_UPC_TB_LDOD - 1.8V
PP3V3_UPC_TB_LDO - 3.28V
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I have a dead FX505D, motherboard FX505DD REV 2.0 , the owner replaced the cmos using a screwdriver and he touched something on the board, since then the laptop its not starting, i have managed to see that U8800 (BQ24780SRUYR) charging IC is getting hot under a thermal camera , i have desoldered it but the laptop still doesn't power on, i also have no voltage at power connector on the board. I also replaced the U8800 but still no power. What should i check next?04-22-2024, 01:21 AM
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