Failed OBDII Readiness Monitors –

The emissions control systems on a vehicle have a number of various sub-systems which evaluate and control the output of emissions on a vehicle. Some systems or “monitors” may only run 1 time per 24 hours, and that’s only if the driver meets the manufacturer’s requirements to cause them to run. Vehicles 1996 & Newer require these for a passing smog check in CA.

#1 – Recent battery change, dead/jumped-battery, disconnection of battery terminals

#2 – Recent manual reset of a check engine light with a scanner

#3 – A fault has occurred in one or more of the emissions systems