Function Explanation (DTC Detection Outline)
WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
- The PCM detects the crankshaft rotation speed based on the crankshaft position sensor signal. If there is a small amount of fluctuation in crankshaft rotation speed due to the effect of combustion of each cylinder while the engine is rotating and a misfire occurs in any of the pistons, the crankshaft rotation speed will change suddenly. The PCM adds the number of changes in sudden rotation speed (misfire rate) to each specified crankshaft rotation speed, and if the misfire rate exceeds a certain value, a DTC is recorded.