Readiness Code
Readiness Code
Read the readiness code
Read off diagnostic trouble codes (DTCs) and the readiness status.
If readiness is "OK" and no diagnostic trouble codes are stored, two cycles have run, i.e. the system's diagnostic functions have run two times without detecting a fault.
Hint: Readiness is reset (to "NOT OK") when the diagnostic trouble codes are cleared or if power is cut off to the engine control module (ECM).
US government information (US only)
The United States Environmental Protection Agency (EPA) has issued a guidance letter, "Performing Onboard Diagnostic System checks as Part of a Vehicle Inspection and Maintenance Program" (EPA420-R-01-015 June 2001), that incorporates various implementation issues associated with OBD-I/M testing. One being that the EPA has revised the readiness criteria to allow states to not reject MY 1996-2000 vehicles with two or fewer unset readiness codes, or MY 2001 and newer vehicles with no more than one unset readiness code. As mentioned herein this is suggested practice. Each individual state may abide by this guidance or enforce state regulations suited to their individual environmental needs. Please consult your State Department of Motor Vehicle for your current I/M testing regulations and procedures.
Select the appropriate remedy depending on this status:
1. If diagnostic trouble codes (DTCs) are stored
2. If readiness is "NOT OK".
3. If readiness is "OK" and no diagnostic trouble codes (DTCs) are stored.
1 - Diagnostic Trouble Code (DTC) stored
2 - Read the diagnostic status for readiness
3 - DONE
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Read the diagnostic status for readiness
Read off the status of the diagnostic functions.
Select the appropriate remedy depending on this status:
1. Readiness for probe diagnostics, diagnostics for heated oxygen sensor (HO2S) preheating three-way catalytic converter (TWC) diagnostics "NOT READY".
2. Readiness for leak diagnostics "NOT READY".
Hint: The diagnostic for evaporative emission control is included in readiness for leak diagnostics.
1 - Carry out TRIP
2 - Quick test of the fuel tank system
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Carry out TRIP
Perform a TRIP following Verifying repairs Verifying Repairs so that the engine control module (ECM) executes a diagnosis for diagnostic functions.
Continue - Read the readiness code
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Quick test of the fuel tank system
Run a quick test of the fuel tank system via the vehicle communication socket.
The engine must be run to operating temperature and then left idling for a few minutes before the diagnostic function for EVAP control can be run.
Select Continue
Continue - DONE
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Diagnostic Trouble Code (DTC) stored
Fault-trace and remedy stored diagnostic trouble codes (DTCs).
Continue - ANOTHER TEST
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