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@SBR7_11
Doesn’t the vehicle’s computer only need to register ~50 miles worth of data without it tripping any check engine lights for the eCheck computer to accept it for testing?
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Nope,, I dont know which method of testing they use up there, but yrs ago they went into OBD-II, and looked at list,, 1 line was for "Number of DTC",, should be "0"... they also look at Readiness Tests,, should reflect "Completed",, this is where the control module has used it various logics to make sure system is inside parameters, be it Evap, Catalyst, and couple other I cant think of currently..
To complete Readiness Tests,, most maker have a guide to drive various cycles for speed - times for each system to complete,, but in real world,, doesnt seem to work,, best to just go drive all over hell and back both city, interstate, idle, accell, decell.. all kind of crap for driving
Back when we had it here, they stuffed a sniffer probe in the tail pipe and did a mapped drive on the rollers.. if exhaust content values clean / correct for drive (load.. cruise.. idle) then we got a "PASS"
Check engine light for most any DTC is "2 Trip Detect",, logic has it that if fault seen in 2 consecutive trips (key cycle),, on come MIL to alert operator we have seen fault,, check it out... Non Fatal codes (not kill cat) will turn off MIL after so many cycle,, and retain DTC in memory for somebody to find
Fatal DTC (misfire) will make the MIL flash,,, this will kill a catalyst due to raw fuel in catalyst which will overheat the honeycomb brick and melt it... Flashing MIL is "REMEDY fault right now" concern