Pilot limits

Not an official result

A test in this pilot is recorded as a shadow validation. It is never an official emissions determination, and it does not replace the test your state requires.

Shadow pilot record — not an official emissions test result.

Supported vehicles

• Fuel: gasoline, hybrid, light-duty only. Checked at sign-up.
• Model years: 2008 and newer. Checked at sign-up.
• Vehicle connections:
  • CAN 11-bit / 500 kbit/s (ISO 15765-4)
  Checked by the app when a test starts, before anything is read from the vehicle. The device's firmware (version 0.5) detects CAN only with 11-bit identifiers at 500 kbit/s. Source: replay-proven default (no bench run recorded)

Not supported in this pilot

• Diesel vehicles. Refused at sign-up.
• CAN with 29-bit identifiers and CAN at 250 kbit/s. The device can't detect them, so when a test starts the vehicle doesn't answer, and the app stops the test and says vehicles the device can't detect are not supported in this pilot. Any other connection not listed above is refused by the app when a test starts. Nothing is recorded in either case.
• Heavy-duty vehicles. Not checked at sign-up. The app stops one when a test starts only if its connection is one the device can't detect or this pilot hasn't proven, such as 29-bit or 250 kbit/s CAN. A heavy-duty vehicle that uses the same connection as a car is not refused automatically, so please don't enroll one.

What a test checks

• The check-engine light (MIL) state.
• Stored and pending trouble codes.
• Readiness monitors.
• That the vehicle's VIN matches the vehicle you enrolled.

These are read from the first engine computer that answers, and only from that one. A test has no tailpipe check, no evaporative (evap) check, and does not read the other computers in the vehicle.

How this is enforced: the server computes the recorded result from these items only.

Evidence and time limits

A result is tied to one phone's hardware key, one assigned device in one vehicle, and one trusted time: the server's clock and the window of the scan session. Photos received outside the program's window are refused.

How this is enforced: the server checks the device signature and the trusted time when a result is submitted, and refuses a result that fails either check.

Security and evidence limits

You sign in with a one-time code sent to your email. NIST SP 800-63B does not accept an emailed code as an out-of-band authenticator, so the sign-in shows that someone could read your email, and nothing more.

What ties a result to where it came from is the hardware key on your phone, which signs every result. It is not the sign-in code.

Illinois context

AirCheck Auto runs this shadow pilot in Illinois. It is not run by, affiliated with or authorized by Illinois EPA.

Results are not sent to the State and do not count toward any Illinois emissions test. This page is updated if that changes.