P0411 -- Secondary air injection incorrect flow detected
Activation requirement CHECK ENGINE lamp:
--After two consecutive tests with failure.
Activation of CHECK ENGINE lamp:
--At start of next trip.
Test to detect fault
--The secondary air injection logic chain is checked if the following conditions are simultaneously satisfied:
• No failure in the electrical activation of the secondary air injection pump
• Closed throttle position recognized
• Engine speed below approximately 850 rpm
• Vehicle speed 0 mph
• Load condition below approximately 60%
• Barometric pressure above 780mbar
• Oxygen sensor control activated
• Secondary air injection pump activated at least once after engine start.
If all conditions are met, the diagnostic module requests "secondary air injection" from the engine control module (via CAN data data bus). The diagnostic module then checks the signal of the oxygen sensor 1 for approximately 6 seconds - it must be continuously in the lean mixture range.