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Readiness Monitor (Certain Markets Only)






Readiness Monitor (certain markets only)
This is a function in Engine control module (ECM) that controls the control module's emission-related sub-system. With the function you can read out if the control module has run all diagnostics for the following sub-systems:
- Misfiring
- Fuel system
- Catalytic converter
- Evaporative emission (EVAP) system
- Heated oxygen sensors (HO2S)
- Other related components
Thus, Readiness refers only to if the diagnostics (tests) have been run or not, not if a malfunction was found or not. If a malfunction is found during the test, a diagnostic trouble code is stored and the malfunction light (MIL-light) is lit.
If the tests are run in the driving cycle without detecting a malfunction, then "Readiness" is immediately generated to OK.
However, if a malfunction is found in the driving cycle, then Readiness is generated to Not OK, and another driving cycle is required where the test is run to generate Readiness to OK.

The following alternatives are possible:
- Readiness is run (OK), no malfunction detected, which means that the vehicle can be approved in a check.
- Readiness is run (OK), with malfunction detected, which means that the vehicle cannot be approved in a check.
- Readiness is not run (Not ok), which means that the vehicle cannot be approved in a check.
Readiness was originally a requirement from the American authority, United States Environmental Protection Agency (EPA), and is used there for Inspection and maintenance test (IM-test) (corresponds to annual inspection). Depending on legal requirements, the function may also be found on other markets.