Laptop HDMI port dead after storm

[marce002]

Hello

I would like someone who can give me some hints about this issue. i was working on the laptop msi gamer GE758sf under stomy night, and when a lighstrike hit my neigbourhouse , hdmi output was cut all of a sudden.. laptop works fine but need to try to repair any cap or what you could tell me can get damaged in this circunstances...i have skills to do micro soldering the problem is that i do not have any schematics or boardview to start to measure the board...

note that the samsung led momitor is ok and working fine with another laptop same cable.

thanks in advance for any help at component motherboard level

[mon2]

Re: Laptop HDMI port dead after storm

Post or link schematics for this logic board if available on this forum. Any other markings on the circuit board?

Locate the hdmi connector. Inspect for any damages to the connector or surrounding parts.

You most likely will have some tiny esd protection diodes and one or more may have been damaged during this event. Such defective diodes may be preventing the port from working.

Do you see any visual damage? Take close up pics and post them in your reply but attached to your post. Do not host them on outside random servers as the links will expire over time.

[marce002]

Re: Laptop HDMI port dead after storm

thanks mon once again. no visual damage after removing case. close up of the connector shows a diode marked as L42 seems to be fine caps around also ok... no schematic or boardview found in entire web for this model ge758sf ...
From connector visible pins i can measure like this: from pin1 to 9 top side res to gnd

0ohm
121k
121k
0ohm
118k
118k
OL
0.855Mohm
0.324Kohm


any other hint will be apreciated...

[SMDFlea]

Re: Laptop HDMI port dead after storm

thanks mon once again.

I have sent you a PM regarding your user account,please read it .

[mon2]

Re: Laptop HDMI port dead after storm

The 3 legged part at D18 looks burnt.

Can you inspect it? Looks like it took some heat.

See attached for reference.

[marce002]

Re: Laptop HDMI port dead after storm

Ok seems to be fine, maybe bad light photo, measures ok in diode mode for both diodes package... close up just in case but seems ok... hope problem will not be in the other side of motherboard---

[mon2]

Re: Laptop HDMI port dead after storm

Are there any other markings on the logic board that may help to identify a schematic ? Perhaps some silk screening ?

Near the HDMI connector (due to very high speed of the interface lines), you may find a MUX (multiplexer) that allows for either the local LCD or external video port to be used. Perhaps this component is defective.

[marce002]

Re: Laptop HDMI port dead after storm

Ok had to remove entire board .. no signs of damage.. board model maybe ms-16p71 ver 1.0 as image says.
close up underside of hdmi also attached ... the dual tiny coil is ok...maybe a fuse in the 5v line, exists?

[mon2]

Re: Laptop HDMI port dead after storm

See attached.

U12 = HDMI IC interfaced to the nearby connector.

It is driving the monitor. Datasheet is attached.

You can confirm if the voltages are reaching this IC.

It is possible that the interface pins on this HDMI IC are damaged. Do check if the HDMI sink (your monitor) is working with another HDMI appliance. Test it with other video sources. Then we know the cable & monitor are not at fault.

From the BV file, do see the PCB pads for ESD protection, yet MSI did NOT stuff the ESD protection parts - to save on cost. The ESD pads are empty on your posted PCB pics.

So it is very possible this IC @ U12 is defective from the storm since the ESD protection was absent - not 100% sure but sounds logical.

Is U12 warm or hot to the touch when powered ON ?

Confirm your BIOS settings to see if they play a role on the HDMI connector use.

If you require a replacement:

https://www.aliexpress.com/wholesale...psort=1&page=1

[piernov]

Re: Laptop HDMI port dead after storm

Diode mode to ground on all pins of HDMI connector.

[mon2]

Re: Laptop HDMI port dead after storm

Diode mode to ground on all pins of HDMI connector.

Excellent suggestion. Thank you.

So it appears that this same HDMI IC is popular with XBOX units. Perhaps you
can source it from a local repair shop as well.

The store on Aliexpress we use and recommend is:

https://www.aliexpress.com/item/1005...d=E1AbinIq8d18

[marce002]

Re: Laptop HDMI port dead after storm

Diode mode to ground on all pins of HDMI connector.

attached all pins red probe on ground and diode mode.


Will displayport share the same u12 chip?

[marce002]

Re: Laptop HDMI port dead after storm

mon can you please provide me the bv board file you posted the image from? monitor works fine and cable too as stated in my first post. interesting the missing protection components to save money msi...i will arrange things to do hot powered tests if i can for now just doing res measurements or diode......

this laptop is mine the one i use every day, im so used to it in dual screen mode so i really need to try to fix it, I wonder if MINI DISPLAYPORT the laptop has can work or shares a posible defective u12 too? because if not i can buy a displayport to hdmi cable adapter and have image in monitor right? thnks again to both of you