The most common point of failure is the USB driver installation. The hardware typically identifies as an FTDI device.
1. Device Manager Verification
2. Manual Driver Assignment Do not rely on Windows Update.
3. Port Configuration Once installed, the device will appear under Ports (COM & LPT) as a USB Serial Port. kess v2 install windows 10 verified
After completing the KESS V2 install on Windows 10, perform this verification test:
Common Error Codes after install: | Error | Meaning | Verified Fix | |-------|---------|---------------| | E001 | USB Driver not loaded | Repeat Phase 2; use USB 2.0 port | | E020 | Firmware mismatch | Re-flash firmware via bootloader mode | | E104 | No COM port detected | Disable internal Bluetooth/WiFi adapters |
To revert later:
bcdedit /set testsigning offand restart. The most common point of failure is the
Windows 10 (especially versions 1709 and later) enforces mandatory driver signature verification. The KESS V2 interface (particularly clone units) relies on older, unsigned drivers (often dated 2009-2012). Without proper steps, Windows will block installation, leaving your device showing as "Unknown USB Device (Device Descriptor Request Failed)."
KESS v2 uses CP2102 USB-to-serial chip.
After restart, plug KESS v2 into USB (powered via external 12V or OBD connection).
Check Device Manager → Ports (COM & LPT) – you should see Silicon Labs CP210x USB to UART Bridge (COMx).
No yellow exclamation mark. This bypasses Win10 driver enforcement completely.
If driver issues persist:
This bypasses Win10 driver enforcement completely.