Code E025, Mat Sensor Circuit High Temp Indicated

NOTE: Test numbers refer to test numbers on diagnostic chart.

Code E025 will set if:

Signal voltage indicates manifold air temperature greater than 275°F (135°C)
A vehicle speed is present
Both of the above requirements are met for at least 16 seconds

Due to the conditions necessary to set a Code E025, SERVICE ENGINE SOON light will only stay on while fault is present.

Test Number 1) If Code E025 is current, ED23 display may be used to diagnose this fault. If the fault is current, ECM will transmit 148°C as the data value. If fault is intermittent, see INTERMITTENTS in H - TESTING W/O CODES article.

Fig 1: Code E025: Circuit Diagram

Fig 2: Code E025: Flow Chart MAT Sensor Circuit (High Temp Indicated)