معايرة الحساس لم تُنفَّذ بعد الاستبدال

A sensor replaced without the calibration or learning procedure the module needs afterwards. The part is correct and correctly fitted — what is missing is the step that tells the module about it, and until that is done the module compares live readings against values belonging to the old sensor.

It produces genuine codes about a healthy system, which is what makes it worth naming. Rationality and correlation faults are the module observing that the new sensor's zero point or range no longer matches what it learned. A fault that begins immediately after a sensor replacement is this until ruled out.

Clearing codes is not the procedure, and this is the trap: the learned values persist, so the codes return within a few drive cycles and the fault reads as a faulty new part. The requirement varies by sensor and vehicle — some learn automatically over a defined cycle, others need a commanded procedure with the vehicle in a specific state. Look it up rather than assuming, since doing the wrong one leaves the adaptation untouched.