Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

[Ariu]

I have a problem with an hp 15-n267sg .
The device was not turning on because a faulty superIO.
After replacing the ITE chip it's working fine but the bios not at all, date and time keeps restarting (00:00:00 /01.01.2013)
and I am not able to make any bios settings change...
I didn't see this kind of strange behaviour on other devices , superIO is soldered properly and tried different bios dumps but same...

The CMOS battery is ok , what else can cause this?
Please help.
Thanks

[mcplslg123]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

The bios flashed is from hp website or random dump from internet?? Check RTCRST# & SRTCRST# to start with. No power attached to the board, only cmos cell inserted.

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

The bios flashed is from hp website or random dump from internet?? Check RTCRST# & SRTCRST# to start with. No power attached to the board, only cmos cell inserted.

i dont think its a bios problem because the original bios was also working, but i can give a try with a bios from hp website as well.

where are RTCRST# & SRTCRST# located in this board , i cant find anything...

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

The bios flashed is from hp website or random dump from internet?? Check RTCRST# & SRTCRST# to start with. No power attached to the board, only cmos cell inserted.

as i thougt its not the bios, with bios from hp website same problem...

[mcplslg123]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

Didnt know its AMD Platform as you just gave model number. AMD' RTC circuit is bit different. You can use search and type RTC in your pdf file and proceed to rest voltages. To begin with voltage on pad G1?? As far as bios is concerned, i too dont dount it but its always wiser to flash with bios from manufacturer's website to rule out bios issue.

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

Didnt know its AMD Platform as you just gave model number. AMD' RTC circuit is bit different. You can use search and type RTC in your pdf file and proceed to rest voltages. To begin with voltage on pad G1?? As far as bios is concerned, i too dont dount it but its always wiser to flash with bios from manufacturer's website to rule out bios issue.

When CMOS cell connected D2 diode measurements one side 0v dropped in diode mode, that cannot be right,
but without the cell is reading 0,2V dropped...

How can short the cmos cell the D2 diode?

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

Didnt know its AMD Platform as you just gave model number. AMD' RTC circuit is bit different. You can use search and type RTC in your pdf file and proceed to rest voltages. To begin with voltage on pad G1?? As far as bios is concerned, i too dont dount it but its always wiser to flash with bios from manufacturer's website to rule out bios issue.

G1 is present 3,2V
But when CMOS battery connected C607 also shorted to ground....

[mcplslg123]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

C607 shoul'nt show shorted to gnd. What is the voltage on D1/D2-Both pins and C607 cap??
01.measure without power, only cmos cell inseted
02.Measure with adapter connected, cmos cell also inserted.

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

C607 shoul'nt show shorted to gnd. What is the voltage on D1/D2-Both pins and C607 cap??
01.measure without power, only cmos cell inseted
02.Measure with adapter connected, cmos cell also inserted.

without power only cmos battery connected:
D1 3V-2.8V
D2 2,8V-0V

C607 2,59V

with power and cmos battery connected:
D1 3V-3.1V
D2 3,1V-3,3V

C607 2,93V

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

C607 shoul'nt show shorted to gnd. What is the voltage on D1/D2-Both pins and C607 cap??
01.measure without power, only cmos cell inseted
02.Measure with adapter connected, cmos cell also inserted.

whats about pin9 of U18 chip?(CLKGEN_RTC_X1)
its showing 0,4V with and without adapter...

[mcplslg123]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

without power only cmos battery connected:
D1 3V-2.8V
D2 2,8V-0V

C607 2,59V

with power and cmos battery connected:
D1 3V-3.1V
D2 3,1V-3,3V

C607 2,93V

Everything is correct here.

[Ariu]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

Everything is correct here.

What else may be faulty?

[mcplslg123]

Re: Hp 15-n267sg Strange behaviour CMOS reset (502) , not a battery fault!

It could be U18 is faulty. You need to check all the pins. You can try removing caps connected to RTC line one by one and see if it helps. The mb can be powered safely without these caps. Worst case scenario could be AMD APU is faulty.