what is the main bios controlling ?

[pecrie]

Hi all ,

I'm working on this MB - HP 4730 - Ramones - 6050 A2465501 - MB - A02

When I plug in the power adapter - the charge amber light comes on for ~ 1sec - then goes off - and right after the white led on DC jack comes briefly on and also goes off.

However the light next to the power switch is on and stays on.But pressing the powr switch the laptop /MB will not start.The led on power switch stays on all the time.

On the keyboard no led is on - they are all off.

I have 3.3 V on the power switch - and it goes to 0Volt and comes back on.

However on the main and ec bios chip there is no 3.3V

So is there something with the bios firmware (and I need to flash the main bios chip ?)

Will do some more tests

[ktmmotocross]

Re: what is the main bios controlling ?

what voltages/restances on power rails u have when on power and when hit power switch

[pecrie]

Re: what is the main bios controlling ?

Well I did some more testing.And I did a resistance measurement on the coils.

With the red lead of DMM on ground I checked the DC in 19.x V - it is 682 V

Coils - L209 = 516 Coils on CPU - U 9416 - 9417 - 9418 - 9435 = 7
3014 = 7 5063 = 14
5059 = 27
30536 = 149 Coil on back of print - L503 = 145
30537 = 153

I also did the same measurement in resistance ( Ohm ) mode
DC jack = 42.7 kOhm

Coils - L209 = 1.680 MOhm Coils CPU -9416-9417-9418-9435 = 12.6 Ohm
3014 = 13 Ohm 5063 = 25.5 Ohm
5059 = 46.3 Ohm
30536 = 960 Ohm Coil on back side L503 = 1.073 kOhm
30537 = 1.160 Ohm

On connecting DC adapter I got 19.xV coming in - to R59 sensing and to some
mosfets.
And I only had voltage on L209 = 2.3V

Now I was trying again and pressing on the MB to feel if something would get hot.And yes , I could feel that the BD82HM65 is getting very very hot.
As well as some caps on the other side of the board.

When pressing and feeling , suddenly the board started to power up.I measured the voltages and they were all there.

I connected the KB and now the Capslock blinks 1 time continuosly.Not sure if I will replace HM65 or repair this board.

Thank you for responding

[Duranitron]

Re: what is the main bios controlling ?

Well I did some more testing.And I did a resistance measurement on the coils.

With the red lead of DMM on ground I checked the DC in 19.x V - it is 682 V

Coils - L209 = 516 Coils on CPU - U 9416 - 9417 - 9418 - 9435 = 7
3014 = 7 5063 = 14
5059 = 27
30536 = 149 Coil on back of print - L503 = 145
30537 = 153

I also did the same measurement in resistance ( Ohm ) mode
DC jack = 42.7 kOhm

Coils - L209 = 1.680 MOhm Coils CPU -9416-9417-9418-9435 = 12.6 Ohm
3014 = 13 Ohm 5063 = 25.5 Ohm
5059 = 46.3 Ohm
30536 = 960 Ohm Coil on back side L503 = 1.073 kOhm
30537 = 1.160 Ohm

On connecting DC adapter I got 19.xV coming in - to R59 sensing and to some
mosfets.
And I only had voltage on L209 = 2.3V

Now I was trying again and pressing on the MB to feel if something would get hot.And yes , I could feel that the BD82HM65 is getting very very hot.
As well as some caps on the other side of the board.

When pressing and feeling , suddenly the board started to power up.I measured the voltages and they were all there.

I connected the KB and now the Capslock blinks 1 time continuosly.Not sure if I will replace HM65 or repair this board.

Thank you for responding

try to trace it using this schematics.... gud luck

https://www.badcaps.net/forum/attach...9&d=1364037899

[pecrie]

Re: what is the main bios controlling ?

@Duranitron ,

Thanks for the schematic - but I had another with another name.
But they look the same.

This motherboard and laptop had been pushed and throwing around I believe.
So , I suspect that the MB suffered some serious shocks.
I think that there is a bad connection between some of the MB layers.

So I will not put more time in trying to repair it.

Many thanks for your help

[Duranitron]

Re: what is the main bios controlling ?

why give up your almost there... you said mobo turns on when you press it.. focus there... or just take time out and go back again try again...failure is when you decide to give up..

[pecrie]

Re: what is the main bios controlling ?

Well to put some nuance to it.This laptop has taken quite some beating.
The palm rest is deformed , the screen lid deformed and cracked.

The bottom housing also has cracks and is damaged.
So , I really think that the MB has taken a hard beating.

And also the BD82HM65 chipset is getting very , very hot.
Just as some caps and other parts.

When pressing on the board , then some contact is made , between the different layers.

So this one is for scrap ...