Hi.
Hopefully its something simple, however worst case you could be up for a new computer or a motherboard.
However, in all likelihood, your hard disk will be fine, as will all your files.
If, in the worst case, your motherboard is faulty, you can simply plug your hard disk into a desktop computer via the SATA connections and copy the files from there, or you can buy a USB enclosure to put it into and recover you files that way.
Anyway, a few things to try:
Remove the main battery first, then disconnect the mains power, and hold down the power button for a few seconds.
Then reconnect just the power supply.
(The batteries have a “smart” circuit that communicates with the mainboard via a i2c SMBUS or similar, and if that locks up, it can cause the unit to fail to power on, even if the power supply is good.)
(If it works, reinstall the battery and retest - if it continues to fail with the battery in it, most likely the battery has failed… or extremely less likely, the mainboard battery charging circuit has a problem.)
If that doesn’t work, I’d try with a known good power supply, or alternatively test your one with a multimeter.
If that doesn’t work, you’ll need to disassemble the unit and remove the BIOS battery from the motherboard for 30 secs or so - its a CR2032 or similar silver watch battery, under the top cover, near where the touchpad sits above.
That will reset the BIOS to defaults, and, if the BIOS was corrupted, should fix the issue.
Here is a tear down guide for your model ( There may be better guides out there though…)
https://www.doovi.com/video/dell-inspiro...
Then retest.
Also check if the LED light (if there is one) on the AC adapter turns off when it plugs in, if it does - there is an internal short… if so, check that none of the USB ports have been physically damaged but looking closely at them - if the positive pin is bent and touching either the USB housing or other ground point, that will create a short.
If one of them is physically bent, you can try to straighten them, or at least make sure they are no longer touching a ground point.
If there is a short, and the USB ports look OK, you’ll need to remove any and all components from the motherboard, and retest - it may be one of the daughter boards, the display itself, or some other component has a short.
If, after removing everything, and there is still a short, it must be in the motherboard, and would require skills to isolate and repair, and may not be viable to proceed with
Assuming there is no internal short, and if all the above fails, I’d re-seat the ribbon cable from the power button to the motherboard.
Then, if that doesn’t fix it, I’d test the power switch with a multimeter and make sure that it is actually functioning.
Its rare that they fail, but they sometimes do.
If still failing, you’ll need to check with a multimeter that power is actually getting to the motherboardconnection - i.e. 19 volts where the cable that runs from the DC port and goes to the motherboard is.
If you are getting 19 or so volts there, then the issue is probably further into the motherboard- often around the two MOSFETs near where the power connects to the motherboard, or the power IC (BQ737 or similar) - and would again require a technician to diagnose and repair it.
Hope this information helps.
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