Start with a clean baseline
Use DeviceOK to collect browser-visible evidence for the usb device, then move to the operating system or manufacturer only when the browser reaches a documented boundary.
Live evidence
Relevant checks
WebUSB Device TestRequest a compatible USB device through WebUSB and display the browser-exposed manufacturer, product, vendor, and product IDs.
→USB Vendor & Product ID CheckRead vendor and product IDs for a WebUSB-compatible device that you explicitly select.
→Device & Browser Information CheckSee browser-exposed screen, viewport, language, CPU-thread class, memory class, connection hints, and platform information without installing software.
→First sequence
Do the high-signal checks before risky changes
- 1
Identify which higher-level device type this is
- 2
Try a known-good cable/port
- 3
Use WebUSB only if the device is compatible
Decision points
What the result should change
If the function works in a neutral deviceok testPrioritize the affected app, permissions, routing or configuration.
If the function fails in deviceok and another trusted pathPrioritize connection, OS recognition, official diagnostics and then hardware.
If the browser cannot access that subsystemUse the OS/OEM diagnostic route instead of interpreting missing browser data as a failure.
Browser can help check
- Request compatible WebUSB devices
- Show exposed VID/PID and product strings
- Test higher-level camera/audio/gamepad APIs when applicable
Browser cannot prove
- Access every USB device claimed by the OS
- Measure USB voltage/current generically
- Repair drivers
Repair boundary
Know when to stop browser troubleshooting
- Avoid firmware/driver downloads from unofficial aggregators.
- Change one variable at a time and retest under the same condition.
- Physical damage, abnormal heat, liquid exposure and battery swelling require appropriate service handling.
Used-device inspection
What to verify before paying or signing off a repair
- Test the exact functions you depend on
- Inspect all ports/controls and included power accessories
- Record pass/fail evidence before purchase or repair handoff