Code 25, Intake Air Temperature High: Notes

WARNING: This page is about a different car, the 1995 GMC Sonoma and 1995 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.

Control module applies and monitors a voltage signal (4-6 volts) to intake air temperature sensor. When manifold air is cold, sensor resistance is high and control module sees a high signal voltage. As air warms, resistance decreases and voltage sensed by control module drops. Sensor resistance can be measured at sensor terminals with harness disconnected.

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

This checks if code is a hard failure or an intermittent condition.
This simulates conditions for a Code 23. If scan tester displays a low temperature, control module and wiring are not at fault.