Cold start Rationality Check

A cold start rationality check of the temperature signal that the ECU receives via the CAN bus is performed by comparing it with the intake air temperature.

A plausibility fault TUMP is set when the difference (positive) between the measured ambient- and the intake air temperature exceeds an upper calibrated threshold.

A signal fault TUMP is set when the difference (positive) between the measured ambient- and the intake air temperature exceeds a lower calibrated threshold.