Previa System Readiness Error

I drive a Toyota Previa myself (though not sure what year) and had a similar issue after clearing codes with an OBD2 scanner. It seems like the onboard diagnostics (OBD) readiness monitors haven't completed their tests yet. Basically, the car's computer needs to run through a series of checks to ensure all systems are working correctly after the codes were cleared. You may have to perform a drive cycle.

A drive cycle? What does that involve?

Yeah, a drive cycle. It's basically a specific driving pattern that allows the car's computer to run all the necessary tests. However, the drive cycle can be quite involved, with specific speeds and durations. Some say you need to bring it to the workshop to have them run it, since you need the exact conditions and a professional diagnostic tool. I did not want to take the risk and simply went to the dealership.

Thanks! Turns out you were right. The guys at the workshop simply reset the system readiness via their computer - cost me nothing!