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HP EliteBook 840 G1 Troubleshooting
Release date September 2013, model number 840 G1
Laptop is overheating
Laptop is releasing a lot of heat and the temperature gauge is running too high.
Ensure the environment is not too hot
Check to make sure the temperature in the room is moderate and not overheating the laptop, place laptop in cooler room if necessary.
Ensure proper spacing around computer
Laptop should be properly spaced from other objects, and vents should not be blocked.
Heatsink and fan need to be clean
If your PC is overheating, you may simply have to dust and get rid of lint off the devices fan and heatsink by using a can of compressed air once the computer has been opened up. Fan and heatsink guide
Fan needs to be replaced
If fan is not moving or has cracked and broken, it may need to be replaced to ensure proper cooling.
Battery doesn't charge
Battery may not accept any charge or is not holding a charge when unplugged
Make sure PC is plugged in
Check to make sure both ends of the cord are plugged in.
Laptop powers on when plugged in, but does not power on or has short life when unplugged, then the battery has gone bad and should be replaced. Battery guide
Laptop won't charge, the light on the adapter does not turn on when plugged in, and motherboard does not receive any charge, use multimeter to determine voltage.
Repair or replace DC jack
If power cord must be wiggled and positioned at a specific angle for the computer to charge, and after a while it may not accept a charge at all, the DC jack must be replaced.
Blue screen of death
Computer doesn’t properly power on and instead only shows a blue screen
If a USB or other external device is plugged in and you then receive a blue screen of death then remove all connected devices and power on laptop.
The computer may start to boot but then shuts down, increased Windows errors or "blue screens of death” the computer may freeze for seemingly no reason, or connected devices that worked before suddenly won’t work, if this occurs the motherboard is bad and may need to be replaced. Motherboard guide
The hard drive should be repaired or replaced if the blue screen of death occurs as well as strange noises emanating from the hard drive occur, first make sure the motherboard in the computer can support the type of drive that you want to install before replacing the existing hard drive. Hard drive guide
Blue screen, computer randomly restarts with no warning, any attempts to install new programs fail or computer performance diminishes as time goes on in the day after it is first powered up, to replace your current RAM check the types the motherboard accepts before beginning replacement. RAM guide
Screen isn’t functioning properly
Loose display cable
Screen varies in brightness, displays jagged lines and exhibits other strange behavior, usually occurs if the computer has been hit or dropped, cables just need to be plugged back in.
Back light is out
Picture flickers, blinks on and off, brightness slowly fades or an odd pink/red color casts to the screen, disconnect the screen backlight lamp connector from the inverter board and connect new one.
Screen is damaged
If the screen is cracked or there are dead pixels, the screen must be removed and replaced.
You aren't getting any display, inverter needs to be replaced or repaired.