HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

[Zibbo]

Hi, LA-B181P will always start only when the CMOS battery is inserted, but display comes in like 1 out of 10 attempts.
When I remove the CMOS battery the white LED on power jack blinks continously and when I press the power button the orange light turns On for 3 seconds and goes out.
3v/5v is present, +RTCVCC is present also present on pin 68 of KBC, PCH_RTCRST# and PCH_SRTCRST# are present. What else can I check?

[mcplslg123]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

Check voltage on main bios pins. Either pin6 or pin7 will show low voltage. Check and confirm.

[Duranitron]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

try to flash the bios with good bios dump. make sure to solder the bios ic cleanly and replace bios battery..try to test the bios ic for failure using erase and verify test data.

[lazybigyan]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

Is it possible to convert discrete to uma please instruct me.
HP ProBook 450-G2 LA-B181P

[Fernon@Repair]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

HP Probook 450 G2, LA-B181P

I have this model ...when power connect auto power on no display.... cpu fan high speed spinning ..3 and 5V Ok what shoud i check 1st

[mcplslg123]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

A lot more to check. Schematic is available. Check all the rails which are coming up or not. IS ram voltage present?? Vcore available? Dramrst# present?? So much to check.

[Mike weissman]

Re: HP Probook 450 G2, LA-B181P REV 1.0 won't start without cmos battery

hi, i have same probleme, you can just replace the battery and it should work's.