The yellow mark vanished. The device name changed to "USB Serial Port (COM4)."
Leo sighed. This was the real ritual. He opened a new browser tab and typed the phrase that thousands of home mechanics had typed before him: elm327 v1 5 usb driver download
He connected the USB to his old laptop, which wheezed to life like an asthmatic donkey. He opened the software that came on a mini-CD—software that looked like it was designed for Windows 98. Nothing happened. The software couldn't see the ELM327. The yellow mark vanished