Diagnostics - The Calculated Choice

Best OBD2 Scanner for DIY Car Owners: 5 Proven Picks

Best OBD2 scanner for DIY car owners: corded scan tool plugged into the under-dash OBD2 port near the pedals

We compared maker specifications, warranty terms and Keepa sales-rank histories to pick five wired and Bluetooth OBD2 scanners for home mechanics.

Bluetooth vs Wired OBD2 Scanner: 7 Essential Checks

by Shahzad

Bluetooth vs wired OBD2 scanner: black Bluetooth dongle beside a corded handheld scanner on concrete near a car tire

See how Bluetooth OBD2 dongles and corded handheld scanners compare on parasitic battery drain, proprietary Ford and GM CAN networks, bidirectional active tests, and cold-weather glovebox reliability.

Check Engine Light Codes: 10 Essential Faults Explained

by Shahzad

Check engine light codes: amber warning lamp lit on the instrument cluster seen through the steering wheel

Learn how 5-character OBD2 trouble codes work, what the 10 most common powertrain faults mean, and how to verify the failed part with live fuel trim and sensor data before buying replacements.