The intake air temperature (IAT) sensor is a thermistor or a variable resistor that measures the temperature of the air entering the engine. The powertrain control module (PCM) supplies 5 volts to the IAT signal circuit through a pull-up resistor. When the intake air is cold, the PCM detects a high voltage on the IAT signal circuit. As the intake air warms, the PCM detects a lower voltage on the IAT signal circuit. If the PCM detects an excessively high IAT signal voltage (low temperature indicated), DTC P0113 will set.
• | DTCs P0101, P0102, P0103, P0117, P0118, P0125, P0502, P0503, P1114, or P1115 are not set. |
• | The engine has been running for at least 10 seconds. |
• | The engine speed more than 50 RPM for 5 seconds. |
• | The engine coolant temperature is more than 0°C (32°F). |
• | The vehicle speed is less than 80 km/h (48 mph). |
• | The IAT sensor signal voltage is more than 4.8 volts. This would be approximately -28°C (-33°F). |
• | The condition exists for less than 1 second. |
• | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
• | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
• | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
• | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
• | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
• | Clear the MIL and the DTC with a scan tool. |
For intermittent conditions, refer to Intermittent Conditions .
Step | Action | Values | Yes | No |
---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate an intake air temperature below the specified value? | -24°C (-11°F) | Go to Step 4 | Go to Step 3 |
3 |
Does the scan tool indicate that DTC P0113 failed last test? | -- | Go to Step 4 | Go to Intermittent Conditions |
4 |
Does the DMM indicate a voltage near the specified value? | 5 V | Go to Step 5 | Go to Step 10 |
5 |
Do both 5-volt reference displays indicate OK? | -- | Go to Step 7 | Go to Step 6 |
6 | Locate and repair the short between the IAT signal circuit and 5-volt reference 1, or 5-volt reference 2. Is the action complete? | -- | Go to Step 15 | -- |
7 |
Does the scan tool indicate an IAT sensor display near the specified value? | 150°C (302°F) | Go to Step 8 | Go to Step 9 |
8 |
Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 13 |
9 |
Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 |
10 | Does the DMM indicate a voltage more than the specified value? | 5 V | Go to Step 11 | Go to Step 12 |
11 |
Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 |
12 |
Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 |
13 | Replace the IAT sensor. Refer to Mass Airflow Sensor/Intake Air Temperature Sensor Replacement . Is the action complete? | -- | Go to Step 15 | -- |
14 | Replace the PCM. Refer to Powertrain Control Module Replacement . Is the action complete? | -- | Go to Step 12 | -- |
15 |
Does the DTC run and pass? | -- | Go to Step 16 | Go to Step 2 |
16 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |