Frequently Asked Questions

Below are some common questions and misconceptions many people have about the california smog requirements

1.)Does my vehicle qualify for smog exempt in california?

Smog inspections are required unless your vehicle is:

  • Hybrid
  • Gasoline powered 1975 year model or older
  • Diesel powered 1997 year model and older or with a Gross Vehicle Weight rating (GVWR) of more than 14,000 lbs
  • Electric
  • Natural gas powered with a GVWR rating of more than 14,000 lbs.
  • Motorcycle
  • Trailer

2.)My DMV registration renewal notice states my vehicle requires a smog check at a STAR station, what does this mean?

If your DMV registration renewal notice states your vehicle requires a smog check at a STAR station, you may still take your vehicle to a Gold Shield or Test Only station before the new program begins.  If your vehicle registration states your vehicle requires a smog check at a Gold Shield or Test Only station, you must take your vehicle to a STAR station after December 31, 2012.

For more information on the STAR program or to find a station near you, visit

3.)How often does my vehicle have to be tested?

If your vehicle is subject to Smog Check, it must be tested every other year. An inspection is also required if you sell a vehicle and when registering a vehicle for the first time in California.

4.)Do I need to take anything with me to my Smog Check?

Remember to take your Department of Motor Vehicles (DMV) registration renewal form with you when getting a Smog Check. This will help ensure that the correct vehicle information and test results are electronically sent to DMV.

5.)How can I help my vehicle pass Smog Check?

Performing regular and proper vehicle maintenance according to your owner’s manual and not tampering with the emissions control equipment are keys to passing Smog Check. If the Check Engine light comes on, take your vehicle to a licensed repair station as soon as you can to have the problem diagnosed. Consult your owner’s manual for repairs that may be covered under your emissions warranty.

6.)What if my vehicle fails Smog Check?

In order to complete your registration, you will need to obtain repairs necessary for the vehicle to pass a Smog Check retest. Before beginning repairs, you may want to find out if you are eligible for the Consumer Assistance Program.

7.)Are programs available to help if my vehicle fails?

Yes. The Consumer Assistance Program (CAP) offers both repair assistance and vehicle retirement to eligible consumers whose vehicles fail Smog Check.

8.)I have a motor home that is very heavy. Is it safe to use the dynamometer for the Smog Check inspection? What should I do?

Motor homes with a Gross Vehicle Weight Rating (GVWR) of 8,501 pounds or more are excused from dynamometer testing. Your Smog Check technician will be able to give any such vehicle the two-speed idle test. Some motor homes with a GVWR of less than 8,501 pounds still may not be safe for dynamometer testing. If your Smog Check technician decides he or she cannot safely test your motor home on the dynamometer, they should write that on your invoice. A State Referee facility can provide relief in these circumstances. Call the Referee Scheduling Center at 800-622-7733 and make an appointment at a Referee Facility. Take your invoice to the Referee. If the Referee inspector agrees, he or she will test the vehicle using a two speed idle test.

9.)I'm planning to register my vehicle as non-operational this time around. Do I still need a Smog Check?

No, the Smog Check is only for operational vehicles. However, if you miss your biennial Smog Check while the vehicle is non-operational, you will be required to get a smog inspection prior to bringing the vehicle back to operational status.

10.)The technician says he cannot perform an ASM (dynamometer) smog test on my vehicle because the tires are worn out. Can he do that?

Yes, anytime the technician feels that the vehicle is not in good enough condition to safely complete a smog inspection, the technician should refuse to test the vehicle.