flash7210 wrote:
Even with my relatively inexpensive android-torquepro-elm327 code scanner, I can clear all the codes (except SRS and ABS) and the check engine light will go out for at least one drive cycle. Then my perpetual p0102 code comes back with a CEL.
But the CEL will at least go out temporarily.
So maybe your Autel isn't actually scanning all the modules like it says it is.
Maybe try purposely setting some codes by disconnecting a ABS sensor or a transmission sensor to see if the device picks up these faults.
The check engine light will only turn on for codes that directly relate to emissions.
My personal record is something like 112 codes in a vehicle and no check engine light,and yes the MIL was working correctly since all 112 codes all dealt with the radio,heated seats,door modules,and the like that have nothing to do with emissions.
There are what they call hard fault codes that not every scanner can make go away no matter what,even with the codes erased the light will still be on since those codes are stored in a different part of the PCM/ECU that alot of scanners can not access.