HDMI or charging over USB C only works if AC is plugged in

[roly445]

Something has just started to happen on my laptop which is really odd so I thought I'd ask on here for some advice.

I have a 13-ah0503na which I use with a Samsung C34J791 and has been running fine, charging and display, for the last 3 months.  Yesterday that changed.

I plugged in the the screen via the USB C connection and no charge or video signal, but the USB pass thru is working correctly so I can use my keyboard and mouse which are plugged into the monitor.

The odd part is if I now plug in the AC power the Samsung gets a signal and is shown the screen. If I then remove the AC power, the laptop stays on change via the USB C and the picture remains on the screen.

The same thing happens with the bundled HDMI adapter, with no picture showing until the laptop is plugged into AC, and once AC is removed it carries on working.

I thought this was just a Windows issue to start with so i powered down the laptop, plugged in the USB C cable and no charge. Plugged in the AC and charge. Pull out the AC and is still charging.

I have now updated all the bios, firmware and drivers and it is still happening.

I have 4 months left on the warranty so I can take it back and get it repaired, but I didn't know if someone has seen this before.

Thanks 

[The_Fossette]

@roly445,

Welcome to the HP Support Community!

I recommend you perform a system restore back to the date when everything was working fine.

Follow the steps in the below article to perform a system restore.

https://support.hp.com/in-en/document/c03327545

Let me know how it goes and you have a great day!

If you wish to show appreciation for my efforts, mark my post as Accept as Solution. Your feedback counts!

Cheers!

[roly445]

@The_Fossette,

Thanks for you response, I should have added to the original post that I have already done this. And it has changed anything.

Also Windows wouldn't be affecting the changing of the device if the power is off, so I don't believe it is a Windows issue

Thanks

[The_Fossette]

@roly445,

I recommend you contact support to further diagnose the issue.

Here is how you can get in touch with support.

1)Click on this link – www.hp.com/contacthp/

2)Select the product type.

3)Enter the serial number of your device or select let HP detect your product option.

4)Select the country from the drop-down.

5)You should see the HP phone support number or Chat option listed.

Cheers!