A BMW OBD cable turned into a Kia diagnostic tool

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A DIY mechanic wanted to diagnose his aunt's 2018 Kia Forte, which clicked but would not turn over. He had an old BMW OBD-to-USB cable that normally only works with BMWs, so he opened a Claude Code session and asked it to get the cable talking to the Kia, with guardrails for safe CAN bus communication.

Claude built its own diagnostics and communication interface, checked battery health, voltages and fault codes, and tried cranking the engine to watch the voltage. Seeing little voltage drop, it suggested a list of checks, including cleaning the starter solenoid terminals. While doing that, the terminal B stud came right off; the post text available here ends before the final outcome.