When all USB ports are not working on dock HAC-007

[Dr-Wily]

Hello there !

I am facing on strange issue whith erlier docking station of the NIntendo Switch. The docking system itself works well, when the console is docked I have an image on TV and all type of wireless controlers (Joycon or pro controler) works and the Dock can charge the console.

But at the same time all USB ports (side USB and rear USB3) are "dead". No charge and no devive detection. Network adapter for example is not detected, same thing for wired controler.

On the PCB HAC-CDH-MAIN-10, I have checked voltage on USB port and I measured a solid 4,990v but not 5v. I can't tell if it's normal but all components around VLI VL120n-q4 chip are good. I don't think this chip is faultly because other dock features may not work... or this chip drive only USB and does not take part in display and link between console and dock.

I don't really understand why USB port suddenly stop working (no detection, no charge) while at the same time those are powered.

How to diagnose this issue ? Many first generation dock are plagged by this stange failure.

Thanks ;)