• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
The intake air temperature (IAT) sensor 1 is an integral part of the mass air flow (MAF) sensor. The IAT sensor is a variable resistor that measures the temperature of the intake air. The engine control module (ECM) supplies 5 volts to the IAT signal circuit and supplies a ground to the low reference circuit.
The following table illustrates the difference between temperature, resistance, and voltage:
IAT | IAT Resistance | IAT Signal Voltage |
---|---|---|
Cold | High | High |
Warm | Low | Low |
• | The ignition is ON or the engine is running. |
• | The ignition voltage is greater than 8.5 volts. |
• | The DTCs run continuously once the above conditions are met. |
The ECM detects that an IAT 1 circuit is open, shorted to ground or voltage.
The ECM detects that the duty cycle of IAT 1 signal is greater than 90 percent.
The ECM detects that the duty cycle of IAT 1 signal is less than 10 percent.
DTC P0110 is a Type B DTC.
DTC P0110 is a Type B DTC.
• | If the engine has sat overnight, the IAT sensor and the ECT sensor values should display within 3°C (5°F). |
• | High resistance on either the IAT sensor signal circuit or the IAT sensor low reference circuit could set a DTC. |
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance, or for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If less than the specified range, test the signal circuit for an open or a short to ground. If the circuit tests normal, replace the ECM. |
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
Test and record the resistance between the signal circuit terminal 3 and the low reference circuit terminal 2 at various ambient temperatures. Compare those measurements to the Temperature Versus Resistancetable and verify that the resistance is within 5 percent of the specification.
⇒ | If not within the specified range, replace the MAF/IAT sensor |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for engine control module replacement, setup, and programming |
Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.
⇒ | If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning. |