California is updating its smog check rules to require all OBD-II readiness monitors to be complete for most vehicles, with very limited exceptions. These monitors verify that emissions systems are ...

View post: Introducing the Men’s Journal Gear of the Year Issue With Keanu Reeves! OBD2 scanners reveal car issues, aiding diagnostics before emissions tests or repairs. California's 2025 rules ...

Stricter smog checks: From October 2025, California will require all OBD-II readiness monitors to be set for a vehicle to pass inspection, with phased exceptions. DIY tools expand: Affordable scanners ...

In March 2022, within a broader-treatment post on automobile owners’ rights to repair their own vehicles, I briefly introduced the topic of the on-board diagnostics (OBD) port, used to monitor (and in ...