Laptop boot fault after flat battery

[antus]

Sounds like power pack, or power supply circuit on the main board. Like its trying to start (or charge) but cant get enough current to do so. Hard to test without another compatible power supply though. If its close to 12v you might have options but most are 19v now.

[immortality]

Still no change. tried other ram modules although they are from an older machine so not sure if they are compatible. with the old ram module it does power up and the screen does not pulse.

The HD is spinning up.

Tried another HD out of my old laptop, it powers up, spins up the HD and then stops again after a few seconds.

Put the original ram and HD back in and exactly as before. powers up, fan spins, HD spins and the screen flashes faintly once per second

Fault is the same with battery and/or power supply connected. Will test with my supply.

[immortality]

I have swapped power backs over. No change at this stage. I'm going to leave it to charge and see what it does. The only other option is to put his HD in my machine as I have a slightly newer version of his machine.

[immortality]

HD seems fine, just plugged it into my laptop using external HD case and it's accessible although his user files are protected so not sure how to access those yet.

[MAGP]

Get a Live CD or Live USB (depending on your boot order). If the unlikely event of the boot loader on the hard drive is faulty a Live CD or Live USB will let the machine boot.

[immortality]

What would happen if I remove the BIOS battery?

[Tazzi]

HD seems fine, just plugged it into my laptop using external HD case and it's accessible although his user files are protected so not sure how to access those yet.

Im able to plug into my old hdd via external sata drive (After swapping to SSD) and don't have problems getting into the files?

[immortality]

OK. so the machine has been on charge for a couple of hours now but the battery light was still showing as charging. Anyway decided to try booting again but before I did I pushed and held the little reset button on the motherboard and now the machine has booted up normally as if it's just awoken from the sleep state with everything open when the problem occurred. We have backed up all the critical files he needs for uni so now I'm shutting it down and waiting to see if the battery charges up correctly.

HD seems fine, just plugged it into my laptop using external HD case and it's accessible although his user files are protected so not sure how to access those yet.

Im able to plug into my old hdd via external sata drive (After swapping to SSD) and don't have problems getting into the files?

Yes, I had the exact same result when I put SSD in my laptop.

[vlad01]

Sounds like power pack, or power supply circuit on the main board. Like its trying to start (or charge) but cant get enough current to do so. Hard to test without another compatible power supply though. If its close to 12v you might have options but most are 19v now.

I was thinking the same thing. Switch mode PSUs do the exact same thing when they fault, they blip on briefly every sec or so in an endless cycle.

I had a few PCs in my time do this but laptops? Do they use DC-DC convertor system? If so I suppose that could do the same as a switch mode.

[vlad01]

What would happen if I remove the BIOS battery?

nothing much other that setting reset, time/date , boot priority and what ever minimal things a laptop would allow to adjust.
You could get a "CMOS checksum error, defaults loaded" message, that is if the bios setting were corrupt and causing this issue in the first place.