Toshiba Satellite A100-525 power indicator light disappears on pressing Power Button and voltages disappear except 4.5v on one pin of the battery terminal. Some like L9 shorts to ground and otherwise; capacitors - C340, C371, C98 short to ground, on-board and off-board. Please experts in the house, assist me pin down the fault. See schematic attached.
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Re: Toshiba Satellite A100-525 Power Issue
Hi.
1) Where are C340, C371 caps ?
2) How are you measuring to find the shorts on the caps ?
3) What is the history of the unit ? Liquid damage ? Using original power supply ?
4) C98 = 0.022uf and will not be missed if left off the board. Are you checking with a resistance across the pins ? What is the scale being used on your meter ?
5) Consider to remove all power -> meter in resistance scale (start with the lowest) -> check the resistance to ground of each coil (large grey in color); 2 legs; inductors.
List the inductors and the resistance to ground when found.
6) Study page 5 of the posted schematic.
Voltage of +VADPTR ?
voltage @ Fuse 502, check both pins.
U511 (charger IC), ACDET pin voltage ? This must be > 2.4 volts to identify the external power adapter is capable of powering this logic board.
voltage @ fuse 503, check both pins. -
Re: Toshiba Satellite A100-525 Power Issue
@mon2. Thanks alot for your efforts in assisting me resolve my pc issue. After I read your comments, I had thorough observation of the motherboard I have issues about and discovered that the board labeling does not tally with the schematic in some areas. For instance, I couldn't find F502, F303 and U511 on the board. And I ask, is the schematic I'm working with the one for my uploaded board screenshot? Please, assist me further, Veteran.Attached FilesPremium supporters get full download access and other benefits.
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Re: Toshiba Satellite A100-525 Power Issue
Board is "San Antonio 10E" (AMD chipset) not "San Antonio 10" (Intel chipset).OpenBoardView — https://github.com/OpenBoardView/OpenBoardViewComment
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Re: Toshiba Satellite A100-525 Power Issue
@piernov. Your support helped me alot. I got the right schematic, though I wasn't able to get its boardview. However, I was lucky to figure out a faulty coil. I pulled another one off an old parked laptop board, and that was my saviour. The laptop is up and running as I speak. Many thanks, Super Moderator. Please, assist me in subsequent posts as I am a newbie!Comment
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Re: Toshiba Satellite A100-525 Power Issue
@mon2. Your post in a big way assisted me find solution. Actually, I was wrong with the schematic I sent and you posted in regard. @piernov helped with clue to appropriate schematic for the laptop. VADPTR, ACDET were present. As I was checking the coils on your instruction, I discovered that L9 behaved differently. I pulled it off and replaced it with another I pulled off from another parked laptop board. Then, laptop responded. It's now up and running. Many thanks, veteran.Comment
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Hi all,
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