I got this laptop as a trade and from what I can find, there's no power on the motherboard other than the power coming from the charger. I can find 20v by the charger but no other power rails anywhere else. Is this a bad charging ic or what would cause this. I've used a thermal imager and there's nothing hot.
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1) Review the charger circuit sticky above by piernov - great reading on how charger circuits function.
2) Be sure that the power adapter is suitable for this laptop.
3) Trace the DCin power connector to locate the DCin mosfets. What are their topside markings? The mosfets will be black in color with 8 pins (4 on each side). Following these 2 * DCin mosfets will be a charger IC that is responsible to enable / disable these mosfets. The gate pin # 4 of the mosfets will often be controlled by the charger IC. Share quality pics and/or details of the topside markings of the charger IC.
4) Remove all power -> meter in resistance mode -> measure the resistance to ground of these DCin mosfets. Checking for a low resistance which may confirm that there is a shorted component in the power path of these mosfets -> causing the power supply to be shut off.
5) If available, share a link to the schematic (do not post it here) -> post the schematic in the dedicated schematic forum. -
Yeah so far more than one I've gotten 0 ohm shorts on pins 4 and 5Comment
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IT8299E120A = SIO controller and used for the keyboard + real time clock and few other functions. This is not your charger IC. Review around for a leadless square IC which should be smaller in size than this one. Perhaps is on the opposite side of the mosfets (ie. top / bottom side of the circuit board).
Could be with a 'BQ' markings = Texas Instruments or another brand. Being Asus, chances are slim that there is a schematic for your logic board but we may be able to figure it out without one.
What are the topside markings of the mosfets near the DCin power connector? Using Google, we should be able to figure out if they are N-channel or P-channel type of mosfets.Comment
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And would the ISL9238BH be what you're looking for the ICComment
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ISL9238BH - yes
This is the charger IC for your logic board. No hits on the mosfets. Can you post a pic of this region?
They should look something like the attached:
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Alright here's a few pictures.Attached FilesComment
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Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
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Hi all!
I'm trying to troubleshoot a Microsoft Surface Pro (5th gen) model 1796 that won't power on. Motherboard model is M1007506-015. My priority is retrieving data, but the SSD is integrated so it looks like if I can't repair it it'll need to go to a data recovery company. I've done a little basic board repair before, but nothing this advanced until now. So please forgive my ignorance in advance. 😅
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https://www.badcaps.net/forum/troubl...-hardware-devi... -
Hi all,
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