Diagnostic Aids

Extreme high or low ambient temperatures may prevent EVAP system tests from initiating. Performing a visual inspection prior to running EVAP service bay test may prevent having to repeat the test. A loose fuel cap may cause a service bay test to abort or fail and prevent the I/M System Status from updating. A failed or aborted test will require vehicle to cool down in order to meet the enable criteria to run another test.

The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the required tests have not run. When a failure occurs, the emission related DTC portion of I/M System Status display will indicate that MIL is requested. The I/M System Status also registers the number of DTCs.