HP 4540s CapsLock continously blinks

[pecrie]

S I have this 4540s from HP.When powering on the Caps Lock starts to blink.
The wifi led is orange and the led next to it is white.

I have read that it is something with the power supply.
After a 6 seconds the fan starts to turn slow than high speed.

I did not check voltages at this moment.But I did the 30 sec press power button - took out battery etc.
Nothing is changed.

Looks like there may be some mosfets defective or even the CPU - it should have a i5 - must verify if its the correct one.

So any ideas ??

[caspian]

Re: HP 4540s CapsLock continously blinks

Have you tried another RAM module?

[R_J]

Re: HP 4540s CapsLock continously blinks

You could have a corrupt bios, Seems to be a common problem.

[pecrie]

Re: HP 4540s CapsLock continously blinks

@caspian

I took all the RAM modules out.It makes no difference.Without a keyboard connected , no HDD , no difference.
At start the CapsLock starts blinking.

I will check some voltages , but all seems to be good.Except the power led is not on when I plug in the adapter.
It just briefly lights up then goes out when plugging in the power adapter.

Yes it can be a bios issue too.But first I will check some mosfets etc

[piernov]

Re: HP 4540s CapsLock continously blinks

I have a 4540s where everything works perfectly fine except for DC-in light so I wouldn't rely on it (never found the issue). It goes to amber when charging the battery though
For the caps lock blink usually there is some sort of pattern and it may give some info on what's the issue.

[Udemzy]

Re: HP 4540s CapsLock continously blinks

Flash main bios, bios is corrupt.

[mcplslg123]

Re: HP 4540s CapsLock continously blinks

I have a 4540s where everything works perfectly fine except for DC-in light so I wouldn't rely on it (never found the issue). It goes to amber when charging the battery though
For the caps lock blink usually there is some sort of pattern and it may give some info on what's the issue.

The led in your dc jack is likely to be bad. Did ou tried another dc jack??

[mcplslg123]

Re: HP 4540s CapsLock continously blinks

Flash main bios, bios is corrupt.

Agreed, in most of the cases it is corrupt bios.

[pecrie]

Re: HP 4540s CapsLock continously blinks

On the input jack I have all voltages - 3.3 - 5.2 - 19.2 Volt

The white led on the power jack lights up for 1/2 second then goes off.For very very short time it is also orange.Then no more light.

I can not find the MB number and Version on the pcb board.It is a HP Probook 4540s

The RAM is a 1333 type (don't know if that is correct) -

But for now I want to flash the Bios - Bios chip is >> Winbond 25Q64FVSIG - 1231

Any ideas what type of bios firmware I need for this MB ??

Do you guys know what Intel processors can be fitted in this MB / And RAM ?
Or can you send me to a link with the 4540s specifications ??

Thank you

[SMDFlea]

Re: HP 4540s CapsLock continously blinks

"Or can you send me to a link with the 4540s specifications ??"

Really, all you need to do is google "4540s specifications" .https://support.hp.com/gb-en/document/c03349886

To find the MB number if you can`t find one on the board just search on ebay or aliexpress for "4540s motherboard" ,sometimes in the description will be a motherboard name Compal LA-xxxx or similar,and a picture with the number, sometimes its hidden under a sticker.

[piernov]

Re: HP 4540s CapsLock continously blinks

Motherboard of 4540s is Wistron Richie, schematics is available.
For the BIOS, ask in the BIOS request subsection or search on the forum if good dumps have been posted already.

Also this board may have a dead GPU (216-0833002 I think it was?), they have a high failure rate.


@mcplslg123 it's offtopic but yes I replaced DC-in jack, EC, checked resistor and transistor for the LED and everything is good.

[pecrie]

Re: HP 4540s CapsLock continously blinks

Update on 4540s CapsLock blinking :

@SMDFlea : thank you , yes I did find the specifications for the 4540s via Google.

So , I decided to flash the Bios chip.I used the dumped bin file from SMDFlea with the DMI info in it.
With this firmware the CapsLock blinking was gone , but instead I got the white led in the power jack , that started to blink.

Did the usual checks and tests - 30 sec press power button etc , but it did not help.I also measured some voltages and checked some mosfets.

After this I decided to flash the bios again but now with the bin file from MarcellDJ.And what do you know : it works ..... )))))

I got the no bootable device found - HP UEFI etc .....

So it seems that the bios got corrupted at some point .....

BTW - I found that a blinking white led on the power jack has to do with putting the laptop into hibernation , while there is not enough charge on the battery (this is not the 3 Volts bios battery)

To fix this you must scan the computer with the tool Reimage Repair

http://www.digitaltechglobal.com/hp-...-flashing.html

But I'm not sure if this is an advertisement or a tool recommended by HP

@piernov - the CapsLock was blinking constant ( intervals - so no indication for a specific error )

[SMDFlea]

Re: HP 4540s CapsLock continously blinks

That "Reimage Repair tool " is a scam . You should always try to backup the bios first before flashing,it may/will contain some DMI info, and quite often a corrupt bios can be fixed.

[pecrie]

Re: HP 4540s CapsLock continously blinks

No , I didn't use the Reimage Repair tool.And I did not download it either.
I was not sure if it was a good thing .....

Yes , I made a backup of the Original bios file .....