Solved! inspiron 15 7547 won't start

[docstork]

Dell Inspiron 15 7547 (Intell i7 4510u) suddenly will not power on. It had been working, with poor battery life, and one evening would not. The AC adapter LED is green, and when connected to the laptop the front LED glows white. I have opened the case, removed the battery, and discharged static (power button on for 2 minutes). With the battery not connected, AC plugged in, it will not power on. With the battery reconnected, it will not power on whether AC is connected or not. Finally, I have tried another Del AC adapter with the same results.

Is this definitely a blown motherboard? Is replacement economical? Is there another possibility? If I go the route of motherboard replacement, should I get a new battery at the same time (given increasingly poor battery life)? Any advise and opinions greatly appreciated.

 

[hang-the-9]

Sounds like a bad motherboard, or possibly a back power jack. If the motherboard is worth it, depends on how much it will cost you to replace. I'd say under $200 it may be worth it for that laptop, unless you can find a used working model of the same type for close to that, then I'd just replace the whole thing.

 

[docstork]

Sounds like a bad motherboard, or possibly a back power jack. If the motherboard is worth it, depends on how much it will cost you to replace. I'd say under $200 it may be worth it for that laptop, unless you can find a used working model of the same type for close to that, then I'd just replace the whole thing.

Thanks. The situation has gotten stranger (to me). After a verbal suggestion from a friend of a friend, I removed and replaced the CMOS battery from the motherboard. Now the machine powers on! Clearly this reset the BIOS, and Windows 10 recovered. But does this indicate a weakness either in the CMOS battery (which is a proprietary rechargeable from Dell, not the typical 2032 button) or a possible fault in the motherboard? I would like to walk away fat, dumb, and happy, but my paranoia won't allow it.

 

[hang-the-9]

Sounds like a bad motherboard, or possibly a back power jack. If the motherboard is worth it, depends on how much it will cost you to replace. I'd say under $200 it may be worth it for that laptop, unless you can find a used working model of the same type for close to that, then I'd just replace the whole thing.

Thanks. The situation has gotten stranger (to me). After a verbal suggestion from a friend of a friend, I removed and replaced the CMOS battery from the motherboard. Now the machine powers on! Clearly this reset the BIOS, and Windows 10 recovered. But does this indicate a weakness either in the CMOS battery (which is a proprietary rechargeable from Dell, not the typical 2032 button) or a possible fault in the motherboard? I would like to walk away fat, dumb, and happy, but my paranoia won't allow it.

Sorry, when you said you opened the case and removed the battery I thought you meant the CMOS battery then. If it's working now, let it run, if it fails again, try another battery. I have had laptops that did not turn on boot after a full reset including the CMOS battery removal, in most cases they end up needed a new motherboard. I think maybe one of 4 recovered fully without needing a new motherboard. The rest failed to work once the CMOS battery was replaced or only worked a couple of times before failing again.

 

[docstork]

Sounds like a bad motherboard, or possibly a back power jack. If the motherboard is worth it, depends on how much it will cost you to replace. I'd say under $200 it may be worth it for that laptop, unless you can find a used working model of the same type for close to that, then I'd just replace the whole thing.

Thanks. The situation has gotten stranger (to me). After a verbal suggestion from a friend of a friend, I removed and replaced the CMOS battery from the motherboard. Now the machine powers on! Clearly this reset the BIOS, and Windows 10 recovered. But does this indicate a weakness either in the CMOS battery (which is a proprietary rechargeable from Dell, not the typical 2032 button) or a possible fault in the motherboard? I would like to walk away fat, dumb, and happy, but my paranoia won't allow it.

Sorry, when you said you opened the case and removed the battery I thought you meant the CMOS battery then. If it's working now, let it run, if it fails again, try another battery. I have had laptops that did not turn on boot after a full reset including the CMOS battery removal, in most cases they end up needed a new motherboard. I think maybe one of 4 recovered fully without needing a new motherboard. The rest failed to work once the CMOS battery was replaced or only worked a couple of times before failing again.

Thanks again. I will keep a close eye on it, and if it happens again will immediately suspect the mainboard. BTW, the series 7000 Inspiron 15s do not have an externally accessible power battery. With the very thin design, you have to remove 10 screws, remove the back plate, and then unscrew 5 more screws to unplug and remove the power battery. PIA for what used to be simple.