Note: In Texas, we are allowed (one) NOT READY monitor on 2001 and newer vehicles and (two) NOT READY monitors on 1996-2000 vehicles. Providing you've repaired the cause of any MIL you will need to drive the vehicle until all your sensors show READY. This will cause all the sensors listed in Check 3 above to show as NOT READY. To recap, lets say you' ve either recently disconnected the battery or cleared a MIL. If any of the non-continuous monitors say N/A (Not Available) or N/S (Not Supported), then there is no monitor for that system. If you look at your Vehicle Inspection Report (VIR), you will see the emissions monitors listed and their Ready/Not Ready status. There are three (3) continuous monitors that are always Ready: Misfire, Fuel System, and Comprehensive Components.

As each system completes its own self test, the monitor will set back to Ready.Įffective October 15, 2008: For vehicles year model 2001 and newer, we allow one (1) non-continuous monitor to be NOT READY and still pass the test, but two (2) or more NOT READY's will cause the vehicle to fail.įor vehicles year model 1996 – 2000, we allow two (2) non-continuous monitors to be NOT READY and still pass the test, but three (3) or more NOT READY's will cause the vehicle to fail. This drive cycle relearns the OBDII system and rechecks all of the emissions component's individual systems. In order to get the monitors set back to READY, the vehicle must be driven through a drive cycle, which is a combination of city/highway driving for a set period of time. These non-continuous monitors are considered READY until either DTC's have been cleared with a scan tool or if battery power has been disconnected, then the monitors will reset back to NOT READY. These monitors are like self checks of each emissions component (EGR, O2 sensor, etc) within the OBDII system. If the OBDII system is operating properly, the MIL command status will be OFF. If the MIL command status is ON with a DTC set, the vehicle will fail. If the MIL command status is ON, then the vehicle's Powertrain Control Module (PCM) is commanding the MIL to turn ON, because a problem has been detected within the OBDII system and a DTC has been set.įor example, an engine misfire DTC - PO301.

Check 2 - MIL Command Status and Diagnostic Trouble Codes (DTC's) check.

If the light is not working, the vehicle will FAIL the test, because the purpose of the light is to alert the driver of the vehicle that there is a problem with the OBDII system (exceeding emissions) and the vehicle needs to be diagnosed and repaired. The inspector answers these two bulb check questions as either a PASS or FAIL. The light must come on when the ignition is turned to the ON position and the light must go OFF when the engine is started. This is considered the bulb check portion of the test.

Check 1 - Malfunction Indicator Lamp (MIL) or Service Engine Soon Light, Check Engine Light, Check Engine Symbol check.

The On-Board Diagnostics (OBDII) emissions test for 1996 & newer vehicles consists of the following:

What systems are checked during the OBDII test? These are the requirements for our home state of Texas living in a county that requires emissions testing. Passing OBDII emissions (1996-Present Miata)ĭepending on your local area laws, you may need to pass an OBDII emissions test.

Fuel system monitor drive cycle