Last year, I electrically disconnected my air pump due to a grinding noise. To keep the ("CEL") from illuminating, I connected an old module box blower to the two leads going to the air pump, hoping that it would trick out the computer and cause it to believe the pump was running on first start of the day.
I've had it connected for two days now and haven't seen a CEL. I checked pin 19 and I'm not getting any codes (dtc 4 will usually cause the CEL to illuminate due to an inoperative air pump).
I think it takes at least two trips with the fault before it will set off the CEL.
Is it safe to assume that the experiment was a success if I'm seeing no codes on pin 19? In other words, are the codes leading up to a CEL visible with the home brew tester prior to the CEL illuminating?