PH517-51 won't boot when on battery, getting black screen, boots ok when on AC power.

Try and do a Hard Reset first to reset the EC, Chipset and BIOS chips of your Predator PH517-51 by doing this:

Hard Reset - Remove the HDD and RAM doors first and then remove the sixteen (16) screws from the base cover, then carefully pry up the base cover starting from the opening in SSD bay then grasp and remove the base cover from the PH517-51 laptop.

Then take the RTC/BIOS button battery out and then short this batteries + & - pins with a metal pir of tweezers or a screwdriver at thebattery base and then take the ram module(s) out.

This is the PH517-51 mainboard showing the RTC/BIOS Battery, take the button battery out and shot its + & - pins with metal tweezers to reset the CMOS.

Leave the laptop like that for at least 30min and allow the laptop to reset without any power coming into the laptop board, then reconnect everything, if you have 2x ram modules, only connect 1x ram module and alternate the two ram modules and see if its not the ram that is faulty, as the laptop should turn on and boot properly.

If the above Hard Reset doesn't work then it could be the laptops eDP cable and its plugs that are faulty or the screen is faulty, also with the battery not charging, its probably a fault within the power charging rail that could have its regulator chip shorted or this rail has shorted components and its not allowing the battery, as there are allot of factors why a laptop doesn't charge.

If all these factors are not the cause of your problem, its best to take your PH517-51 to an experienced technician in your area that can pinpoint the exact problem that your laptop has or take it to Acer but Acer technicians will change the mobo as they don't fix mainboards. Good luck and hope this helps you out.

PH517-51 eDP cable if you need to change this cable to get the latop screen to work.

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