Two Trip Detection Logic

Two Trip Detection Logic
When a malfunction is detected for the first time, the malfunction (DTC and freeze frame data) is stored in the ECM memory. (1st trip) The malfunction indicator lamp will not light up at this stage.
If the same malfunction is detected again during next drive, this second detection causes the malfunction indicator lamp to light up. (2nd trip)
The "trip" in the "Two Trip Detection Logic" means performing of the "DTC CONFIRMATION PROCEDURE". Specific on board diagnostic items will light up or blink the MIL even in the 1st trip as shown.