Signal Wave Form

Fig 1: DTC P0112 Signal Wave Form

Courtesy of KIA MOTORS AMERICA, INC.

IATS and ECTS signals should be smooth and continuous without any sudden changes. When the engine is cold, IATS and ECTS signals should look similar, depending on the ambient air temperature. After warmed-up the IATS signal should not have changed less significantly while ECTS signal should have dropped. This indicates the normal increase of the engine coolant temperature is larger than the normal increase of the intake air temperature as the engine warms up.