$01/$01 Readiness Flag Status
MODE $01, PID $01 represents the Readiness Flag Status for Engine Computer (7E8) and Transmission Computer (7E9). Readiness flag status indicates that each flag has completed testing at least once since the memory was last reset. Each Readiness Flag consists of one or more individual monitor tests. Once all required monitor tests are complete, the Readiness Flag Status will display "Complete". This information can be used to verify a repair by running specific monitor test(s) and watching the readiness flag flip to COMPLETE. State emissions inspection programs also use it as one requirement to pass or fail the OBD part of the inspection. For the engine computer (7E8), the Readiness Flags are divided into two groups:
- The first group is called Continuous and includes misfire, fuel system, and comprehensive components. This means that they run their monitor tests continuously on each trip when the enable criteria are met. They will be Supported for all vehicles.
- The second group is called non-Continuous and includes the Catalyst, Heated Catalyst, Evaporative Emissions, Secondary Air, Gasoline Particulate Filter, Air Conditioning, Oxygen Sensor, Oxygen Sensor Heater, and the Exhaust Gas Recirculation (EGR) or Variable Valve Timing (VVT) systems. This means that they run their monitor test(s) once per trip when the enable criteria are met. If the system is failing, the computer may repeat the test several times to determine if the system is actually failing. Disregard the Complete status for the Readiness Flags that are not supported.
This example shows the "Monitors Complete Since DTC Cleared" status for the engine computer (7E8). Once completed, they can only be reset to Incomplete by performing a MODE $04 diagnostic clear, removing power from the computer, or reprogramming the computer.
For the transmission computer (7E9), only the Comprehensive Component Readiness Flag is supported. Disregard the Complete status for the Readiness Flags that are not supported.
