A technician wants to check the results of onboard diagnostic tests for components after a vehicle has failed an emissions test without any trouble codes. Which mode is appropriate?

Mode 6 is the appropriate mode for a technician to check the results of onboard diagnostic tests for components after a vehicle has failed an emissions test without any trouble codes. This mode provides a detailed view of the status and performance of individual vehicle components and systems, especially those related to emissions.

When a vehicle fails an emissions test but does not generate any trouble codes, it suggests that the components may still be functioning within expected parameters but might not be performing optimally under specific conditions. Mode 6 allows the technician to evaluate the monitoring results and test history for each monitored component. This can include data from various tests, such as the oxygen sensors or catalytic converters, which are critical for emissions control.

By using Mode 6, the technician can gather valuable information that can help diagnose the underlying issues causing the emissions failure. This data can indicate whether the components are close to failing, providing insights that may not be captured by the standard trouble codes, thus guiding further repairs or adjustments needed to meet emissions standards.