HP 355 G2 Left USB Ports and Ethernet Port not working

[mon2]

The motherboards will often use electrolytic caps with a polarity - look for silver round caps with a '+' symbol. Alternatively, could be tantalum black caps with a '+'. Post pics. You will not be able to measure the cap since you are observing a short on VBUS. Meter must be in capacitance mode to measure capacitance - if it is not shorted.

[SMDFlea]

I measured a connection to ground on all three Vout pins.

In the schematic there is a Typical application circuit. It shows pins 6,7 and 8 ( Voltage out) are joined together, and there`s a 1uF capacitor between VOUT and ground GND. Remove that cap , and check if the short has gone

[FriedFred]

Post #8, photo 2: PAD6100, directly under the coin-cell battery, and the following power distribution switch, can be of interest.

[Fluxi_77]

In the schematic there is a Typical application circuit. It shows pins 6,7 and 8 ( Voltage out) are joined together, and there`s a 1uF capacitor between VOUT and ground GND. Remove that cap , and check if the short has gone

Hi, I removed this cap but the short still appears... Do you think voltage injection would be useful here to find the faulty item or is it too risky? If not how much voltage and amps would be safe?

[Fluxi_77]

Post #8, photo 2: PAD6100, directly under the coin-cell battery, and the following power distribution switch, can be of interest.

I measured around there but I can't find a short in that region....

[Fluxi_77]

It was this guy... Can anyone tell me what this is and what I can replace this with?

[mon2]

Looks like a typical TVS esd protection array. Flux and remove it and test again without this part. Does the port now function ok?

[Fluxi_77]

I removed D2400 and the short is gone... I did not want to try to turn the laptop on because I did not know what type of component that is and if it is needed.

[mon2]

This is a TVS protection diode array. In the event of a surge from static electricity or similar (ie. walking across a carpet), this excessive surge event will cause this device to trigger and shunt the high level of energy to ground. In the process, this diode dies and must be replaced. Once the part is removed, the protection is lost and a repeated event can cause the same energy to travel further onto the logic board.

Ground yourself by touching anything mated to ground / cold water pipe. Then power up again and test if the USB port is working. Once at the office, can search for replacement parts for the same.

BTW: Almost 99.9% of the offshore USB host adapters are lacking this same protection. We use them often in our designs and have had zero failures with the multiple levels of protection onboard.

[Fluxi_77]

I looked at my only other HP motherboard I have but I did no find any component exactly matching this one and in the internet I also don't find anything when I type k6W 33 so I dont know what to replace it with...

[mon2]

What color is the plastic insulator of the USB connector linked to this defective part? Is it black or purple?

If BLACK, the port is USB 2.0 speed.

If purple / burgundy, the port is USB 3.0 speed.

The color will define the max capacitance of this protection device.

A part like this should work fine here:

https://www.mouser.com/ProductDetail...pzq1vShw%3D%3D

and

https://www.mouser.com/ProductDetail...dKauqwrg%3D%3D

* there are many many others that will also drop in replace the original

[Fluxi_77]

What color is the plastic insulator of the USB connector linked to this defective part? Is it black or purple?

If BLACK, the port is USB 2.0 speed.

If purple / burgundy, the port is USB 3.0 speed.

The color will define the max capacitance of this protection device.

A part like this should work fine here:

https://www.mouser.com/ProductDetail...pzq1vShw%3D%3D

and

https://www.mouser.com/ProductDetail...dKauqwrg%3D%3D

* there are many many others that will also drop in replace the original

Thanks a lot It is black so should be 2.0 so both of these should work?
And what is the best way to buy them because mouser.com and these websites charge like 20€ for delivery if I don't spend more than 50€ while the part itself only costs a few cents.

[Fluxi_77]

Also the ethernet port is still not but there I think it is a mechanical port problem because I get the 3.3V on the port and when I press the cable hard into the board and wiggle a bit I see the orange LED blinking for a few seconds and when I let go it stops blinking. There I also have difficulties to find a replacement because this one has 12 pins 8 for the standard ethernet things and other 2 on each side for the LEDs I believe. So I am not sure where to find one. Or if I should just buy a faulty donorboard on ebay for 30€ where I can take the ethernet port and also the k6w 33 tvs diode.. The port looks like in the image and at the back there is written "DEREN 15154AC" but I can't find anything if I search for that.
What do you guys think?

[mon2]

The TVS part is a jellybean part and can be crossed to literally hundreds of vendors. From where do you source your electronic parts? Suspecting that most mainstream vendors will charge a min shipping fee. You may be able to receive as a sample with TI.COM website. Often the sample parts are shipped from Digikey or Mouser - for free.

If you are not in a rush, Aliexpress should be ok for this component. Just select a high rated shop before purchasing. Mainstream distribution is always preferred, if the parts are available and at fair pricing. Then you are assured the part is not a pull-off; defective; fake / dud or blank.

The idea of sourcing a donor board is an excellent one since you should be able to source this TVS part AND perhaps this oddball ethernet connector. Can you share a front side face of this ethernet part?

There are many permutations of such connectors and this may be a mid-mount ethernet port where the plastic housing is 50% below the PCB & 50% above the PCB for the casing.

Any symbols or part markings on the plastic housing? This may allow us to hunt down the true vendor and part #.

[Fluxi_77]

I am just a hobbyist so this is basically one of the first repairs I did so I don't have a common supplier of parts. And I am also not in a rush so aliexpress would be fine if I would pay less than the 30€ I would for the donor board. Down are the other two sides of the port. Maybe it helps finding it.

[mon2]

Yes, Aliexpress will be a much lower cost option for the parts.

Can you post the topside markings in text? The pic is blurry.

Appears to be stamped with 'DEREN' and then a part # on the RJ45 connector.

==

Yes - Shenzhen Deren is a manufacturer of such RJ45 connectors.

https://www.deren.com/productshow.aspx?id=591

[Fluxi_77]

Yes there is written DEREN 15154AC.
I also found this list on the DEREN website https://manage.deren.com:899/static/...3804990222.pdf and it should be either the 1 or 4 one here with LED depending on the exact measurements...
But where could I find this exact part then?

[mon2]

For the ESD TVS diode, you can source this part:

https://www.aliexpress.com/item/1005...Cquery_from%3A

Be sure to note the location of the corner dot on the topside markings. This corner dot is for pin # 1 identification.

[Fluxi_77]

For the ESD TVS diode, you can source this part:

https://www.aliexpress.com/item/1005...Cquery_from%3A

Be sure to note the location of the corner dot on the topside markings. This corner dot is for pin # 1 identification.

Yeah thank you
From here: https://it.aliexpress.com/item/10050...-specification
The H one looks pretty similar from the pin perspective but I dont have exact measurements so its difficult to say if it will fit...