HP Pavilion 14-CE (DA0G7AMB6D1) - Caps Lock Blink Code 3-2

Hello all

i have a few HP Pavilion 14-CE (DA0G7AMB6D1)motherboards all with the same problem. I have HP cap lock error code 3 long 2 short blinks. (The embedded controller times out waiting for BIOS to return from memory initialization.).

I have tried new RAM, programmed a new BIOS and EC. But still the problem is there. I have 1.2V on the RAM coil, and voltage is on all coils. The laptop responds to the power button but just stays at a blank screen with the 3-2 cap lock blnk code. It consumes around 0.47mA on the power supply.

Does anybody know where else to check or had similar problem, any help would be great?

Thanks

Hello!

Measure the voltages to ground on all pins of BIOS chip, when the machine is turned on.
Do you have an oscilloscope?

Hi matic

Thanks for the help, the voltage to ground on the BIOS pins is

1= 3.39v
2= 3.39v
3= 3.39v
4= 0
5= 0
6= 0
7= 3.39v
8= 3.39v

I do have an oscilloscope but it is just one of those cheap diy kits, so i dont know if it would be very good.

Check with oscilloscope, if you see any pulses on pin 5 of BIOS chip immeadiately after turn on the board with the power button.
Set the time base to 100ms/div, if you have this option.

Ok, i set up the oscilloscope. When i put the probe onto pin 5 and press the power button, i can see pulses of 3.3V that last around 3seconds about every 2-3 seconds.. but the laptop does not switch on.. But when i take the probe off of pin 5 the laptop will switch on with the same 3-2 caps lock blink code.

Ok. The schematic for this board is currently not available, so the further diagnostic is not easy.

Unfortunately this issue may be caused by a damaged APU hybrid. You can try to reflow it.

ok, yes i have not been able to find anymore information about the issue online. It seems that it may be some kind of manufacturing problem. I have 5 of the same boards with exactly the same problem. all CPU voltage is present too.

Is getting the 3.3v pulses on pin5 once power button pressed normal? and then goes to 0v

Do you have best advice for reflowing the APU?

KenM0560 napisał(a):Is getting the 3.3v pulses on pin5 once power button pressed normal? and then goes to 0v

Yes.

KenM0560 napisał(a):Do you have best advice for reflowing the APU?

You neead a BGA rework machine. It is need to remove the glue around the APU before reflowing it. I suggest to use a quality liquid flux for the reflow.

I do not have that equipment. I guess i can not go further.

Thank you for taking time to help.

KenM0560 napisał(a):I do not have that equipment. I guess i can not go further.

If you try to reflow the APU without BGA rework station (with a hot air gun or something else) there is a high possibiltiy to permanently damage the APU or/and the board itself.

Yes it is best i dont try that. i will hold on to the boards for a while just incase the schematics get leaked and can diagnose further. Thanks

I'm not very good at electronics, but looking around if someone had my same problem, I found this post ...
So I wanted to share the "solution" that I found ... Basically the RAM slot is defective. In fact, if you try to lightly hold the RAM bank towards the motherboard, you will see that the notebook starts ... Clearly the perfect solution would be to resolder the slot.