ELM327 clones vary in quality. Prefer firmware that supports the modes you need, stable Bluetooth pairing, and sane timeouts—cheap adapters often drop connections under full live-data load.

Typical steps: locate the OBD2 port (usually under the dash), plug in firmly with the ignition appropriate for your vehicle (often ON/engine running only when the manual says so), pair or connect USB, then open your scanner app and run an adapter test.

If pairing fails, remove old Bluetooth entries, power-cycle the adapter, and avoid simultaneous connections from multiple apps. Wi‑Fi adapters may require joining their network or split-tunnel setups on some phones.

After connection, read VIN (if supported), scan for codes, and sample a few PIDs to confirm throughput before long logging sessions.