Hip Probook 4310s caps lock blinking 5 times.

[Ramee]

I got hp probook 4310s here, when I power it up, it boot but won't continue, just stuck on Hp logo.

Caps lock flashing 5 times every two seconds then stop flashing after four attempts.

1.Replaced cpu with a known good one.
2.Memory
3.Hard drive but no luck.

Tried to power it up with cpu, memory and HDD only but still the same and I can't go to bios settings.

Anyone had experienced this kind of problem?

[dellxps15]

Re: Hip Probook 4310s caps lock blinking 5 times.

first there is a nec tokin.... second could be southbridge.

change that nec tokin with 4 tantalum, then if still the same, reball southbridge.

[Ramee]

Re: Hip Probook 4310s caps lock blinking 5 times.

Thank you for your reply dellxps15.

I will try the tokin first, i'll post back the result.

[highpulse]

Re: Hip Probook 4310s caps lock blinking 5 times.

well if it hang on post , i dont believ would b a nec problem , altough on battery it should run and past logo . i believe more on a corrupted bios , reflasdh bios or even replace the entire rom and insert a new bios on it . it should work fine then

[Ramee]

Re: Hip Probook 4310s caps lock blinking 5 times.

I'll try to change both nec and rom, i already ordered them, i'll probably be here in a

week. I'll well let you guys know.

[Ramee]

Re: Hip Probook 4310s caps lock blinking 5 times.

I already changed the tokin and the rom chip no change.

I checked the smd cap in the middle of the cpu socket it was shorted so I desoldered it, after that i checked the pad for short and it was shorted, so I followed the rail and I ended up to cpu socket.

The cpu socket was shorted 41 ohms; this rail is connected to smd cap in the middle.

Reflow/reball is still beyond my knowledge.

Thank guys for your help

[ravi_1617]

Re: Hip Probook 4310s caps lock blinking 5 times.

It will show shorted with CPU when in socket, check without CPU ,

[ravi_1617]

Re: Hip Probook 4310s caps lock blinking 5 times.

Reflow south bridge

[Ramee]

Re: Hip Probook 4310s caps lock blinking 5 times.

It will show shorted with CPU when in socket, check without CPU ,

With cpu on, tokin is shorted and the mosfet, without cpu 220uf cap in the middle shorted all the to the socket.

I don't have machine to do reflow/reball.

Have you fixed one like this before?

[ravi_1617]

Re: Hip Probook 4310s caps lock blinking 5 times.

yes tokin is fine .press the souh bridge bga with hand (thumb) & start the board.

[Ramee]

Re: Hip Probook 4310s caps lock blinking 5 times.

I already returned the laptop to the owner. Thanks anyway!