Dead HP ProBook 450 G1 - Where should I start looking for hardware defects?

[hitimr]

Hello,

I was asked to try to repair the Notebook (HP ProBook 450 G1) of a relative. 

• The device does not boot at all
• pressing the power switch has no effect
• there is no fan-spin
• Unplugging the battery or removing the small battery and performing a CMOS reset has no effect either
• If the power adapter and/or the battery is plugged in a blue LED is blinking next to the power plug

I suspect a hardware failure, but since the device no longer has warranty I want to try to fix it myself first before sending it in.

So my question is:

Where should I start looking for defects? Are there any parts in this device that are known to likely have failed after 5-6 years of use? 

[WAWood]

@hitimr 

We're not HP Tech support -- we don't have the information to walk you through examining the laptop to look for hardware failures.

To determine the cause with hardware failures, you have to be able run diagnostics. We have no way of accessing your PC from here, so we can not do that for you. You have to do it yourself.

You do this by pressing the Esc key repeatedly when rebooting and then, when the HP Startup Menu appears, selecting Diagnostics (usually F2) and letting it run.

If it is NOT possible to run diagnostics, or if that does not work, then there is NOTHING more you can do by yourself -- and there is NOTHING we can do because we have no way of accessing your PC from here to run diagnostics or repair hardware.