Failed a Smog Check in California? What to Do Next
If your car fails a California smog check, keep the Vehicle Inspection Report (VIR) the station gives you, have the problem fixed at a licensed smog repair station, then retest. You cannot renew registration until the car passes. If repairs are expensive, the Consumer Assistance Program (CAP) from the Bureau of Automotive Repair may pay for part of them or buy the car for retirement.
Why do cars fail the smog check?
| Reason on the report | What it usually means |
|---|---|
| Check engine light on (MIL commanded on) | The on-board computer has stored a fault code. Any lit check engine light is an automatic fail. |
| Readiness monitors incomplete | The car's self-tests have not finished, often because the battery was disconnected or codes were cleared recently. |
| Visual inspection fail | A required emissions part is missing, modified or disconnected, or an aftermarket part is not approved for California. |
| Functional test fail | For example a leaking gas cap, a faulty EGR system or an ignition timing problem. |
| Tailpipe emissions too high (older cars) | HC, CO or NOx above the limit, often from worn spark plugs, a vacuum leak or a failing catalytic converter. |
Step by step after a fail
- Keep the Vehicle Inspection Report. It lists exactly which part of the test failed. A repair shop needs it.
- Get a written estimate from a licensed smog check repair station. California law requires a written estimate before any work starts (see your auto repair rights).
- Check CAP before you pay. If you qualify, the state pays part of the repair, but only for work done at a CAP-contracted station after you are approved. Read the CAP guide.
- Drive the car after repairs. If codes were cleared, the readiness monitors need normal driving (often a few days of mixed city and highway driving) before a retest.
- Retest. Once it passes, the station sends the certificate to the DMV electronically. It is valid for 90 days.
When to use a Smog Check Referee
If you disagree with a result, if your car has an engine swap or unusual configuration, or if no regular station can test it, the Bureau of Automotive Repair's referee network decides. Book through bar.ca.gov.
Find a station for your retest
- Smog check in San Jose — 2 listings
- Smog check in Anaheim — 1 listing
- Smog check in Los Angeles — 1 listing
- Smog check in Sacramento — 1 listing
- Smog check in San Diego — 1 listing
- Smog check in San Francisco — 1 listing
- Smog check in Santa Clara — 1 listing
- Smog check in Sunnyvale — 1 listing
Frequently asked questions
Can I renew my registration if my car failed smog?
No. The DMV needs a passing smog certificate on file before it will renew a registration that requires one. You can pay the registration fees on time to avoid late penalties, but the new sticker is issued only after the car passes.
Is the retest free after a failed smog check?
It depends on the station. Some include one free or discounted retest within a set number of days; others charge the full price again. Ask before the first test.
What is a Smog Check Referee?
A state-contracted facility that handles cases regular stations cannot, such as disputes over a result, vehicles with engine changes, gray-market or kit cars, and vehicles that cannot be tested normally. Appointments are made through the Bureau of Automotive Repair.
Will a check engine light make me fail?
Yes. A lit check engine light is an automatic fail in California. Fix the cause first, and do not disconnect the battery or clear codes right before the test: the car needs to complete its readiness monitors through normal driving.
Related guides
- How to Pass a California Smog Check: 10 Checks Before You Go — A practical pre-test checklist: check engine light, readiness monitors, gas cap, oil change, warm engine and the mistakes that make good cars fail.
- California CAP: Get Help Paying for Smog Repairs or Retire Your Car — The Bureau of Automotive Repair's Consumer Assistance Program pays part of smog repairs or buys failing cars for retirement. Who qualifies and how to apply.
- Check Engine Light and Readiness Monitors: Why Your Car Is "Not Ready" for Smog — Why a car shows "not ready" for smog after a battery change or repair, how a drive cycle completes the monitors, and how many can be incomplete.