California emissions inspection: OBD readiness rules
Smog Check (BAR) plugs into the car's OBD2 port and checks its readiness monitors, the self-tests the engine module runs while you drive. Here's how many may still be not ready.
| Monitors allowed not ready | 1996 to 1999: 1 not ready 2000 to 2018: 1 not ready, and only the evaporative system |
|---|---|
| Check-engine light on | Fails |
| Model years tested in 2026 | 1996 to 2018 |
| Where | statewide |
A rule from Oct 2025 requires every monitor ready; the state is phasing it in.
Official source: Smog Check (BAR) (checked October 6, 2026). States change their rules; check there before you go.
Check your BMW before you go
In the AutoLingo for BMW app, pick California under Settings, "State for emissions testing". Connect, and the Overview's "Inspection in California" line says whether the car would pass, would not pass, or isn't tested, with the reason (for example, which monitor isn't ready). Step by step: check if your BMW is ready for an emissions inspection.
Monitors not ready? Follow BMW's drive cycle (about 25 minutes from a cold start), or drive normally for a few days, city and highway, and check again. They reset when the battery is disconnected or the fault codes are cleared, so don't clear codes just before the test.
Coming soon
Enter your email address to hear when AutoLingo for BMW is ready.