HP Pavilion 14-EK (213224-1Q) Excess current draw after adapter plugged in

Hello

I have 3 HP Pavilion 14-EK motherboards that are all showing the same symptoms. When the adapter is plugged in there appears to be excess current draw, after plugging in the adapter 400mA - 500mA is drawn for around 5 seconds then it drops back to a more normal looking 100mA. Then the board will power on after pressing the power button and does work normally, but it will shutdown randomly, looking at the current consumption there does look like more is being drawn when the board is switched on. The rating on the bottom of the case is 2.31A, but i am seeing more than that when powered on even without the battery connected and charging.

I have made a video of the power-supply to explain better and the EC and PCH area with a thermal camera. See attached image of the resistance measurements on all coils, they appear normal. Circled in yellow are the areas that are heating up during the excess current draw.

EC = Nuvoton NPCE48ALA1BX
3.3v IC = DFAFMB
3.3v LDO = 36k ohms

KenM0560 wrote:after plugging in the adapter 400mA - 500mA is drawn for around 5 seconds then it drops back to a more normal looking 100mA

Hello!
According to your video, the current consumption is 0.04-0.05A (40-50mA) and then drops to 0.01A (10mA).
This seems completely normal to me, because you connected the power supply to the board without the battery connected. Therefore, the CMOS was cleared, and after applying power, the board automatically started the configuration process for a few seconds and then shut down.

KenM0560 wrote:The rating on the bottom of the case is 2.31A, but i am seeing more than that when powered on even without the battery connected

Please, post a video of your service power supply when you turn on the board.

According to your video, the current consumption is 0.04-0.05A (40-50mA) and then drops to 0.01A (10mA).

My apologies, i did mean 10 - 40 -50mA.

Please, post a video of your service power supply when you turn on the board.

this is with No battery connected.

15sec - Pressed power button
57sec - cmos reset message
1:22 - Windows loaded to desktop
1:26 - crashes

when running on battery alone, it does seem to be stable

Does the machine also crash, if you leave it running in BIOS without a hard drive?

With the SSD removed and left running in BIOS it does seem stable, i left it for 10-15 minutes with no issues/crashes.

Current draw was stable and around 1.24A with no battery connected.

Try to boot Linux Live from a USB stick. Does the machine crash in this case?

It has been running ok from a linux live usb for about 15-20mins all as normal. Do you think its a bad SSD?

Try with another HDD (or SSD) with a freshly installed OS.

This morning i attempted to install a new SSD to install a clean Windows install and the laptop does not even POST anymore! It will stay on for maximum of 8seconds then shuts down. It has only been sitting on the desk all weekend. Even with SSD removed it fails to POST now.

Measure the voltages to ground on all coil for a short time when the machine is turned on.

Please see attached picture with voltage measurements. Now the board will only stay on for around 3-5 seconds after pressing the power button and consumes 50mA before shutting off. SSD was present and no battery.

- Remeasure the resistance to ground on coil PL5101.
- Please, post a clear picture with visible markings on the chip PU5101.

Resistance to ground on coil PL5101 = 139 ohms (looks to have dropped from 174 ohms after the initial measurements)

PU5101 markings are Z236 5416

Measure the voltages to ground on pins 2, 3, 4, 5, 6, 7, 19, 23, 24, 25, 29 of chip PU5101 for a short time when the machine is turned on.
Chip PU5101 pinout:

PU5101
2 = 0v
3 = 3.3v
4 = 26mV
5 = 0v
6 = 0.7v before power button (0v after power button)
7 = 5v
19= 13v (before and after power button)
23= 4.6v
24= 0v
25= 0v
29= 0v

Were you able to find the manufacturer/model of the IC and datasheet?

Try to reflash the BIOS chip. Don't forget to save the old dump.

I have programmed a "fresh" bios bin from the HP softpaq matching the backed up bin F.04 08BF6 with no dmi information. I used NeoProgrammer to program the chip, however there was not a profile for the BIOS chip onboard MX77L12850F, so i used a Winbond 25Q128JV profile and it went ok.

The laptop did power on with more current than before (60mA), and looked to reset the CMOS etc, and it did POST but it crashed a few seconds later when entering the BIOS settings screen. Also when pressing the power button there is a slight delay with the current, it takes a few seconds to startup if you understand, i can make another video to show if needed.

It seems to be going further than before but still is unstable, sometimes it wont POST other times it gets half way through loading Windows and crashes.

Try to reflow the APU hybrid.

Unfortunately i do not have the equipment to work with the larger BGA chips. Do you suspect some solder balls have cracked/disconnected under the APU?

I suspect that the APU is more likely internally damaged (bad connection between the silicon core and substrate), which reflow sometimes confirms (APU starts working again after reflow, but only temporary).