2001 Chevrolet/Geo Camaro  

DTC P0113

Circuit Description

The intake air temperature (IAT) sensor is a thermistor which measures the temperature of the air entering the engine. The powertrain control module (PCM) applies 5 volts through a pull up resistor. When the intake air is cold, the sensor resistance is high and the PCM will monitor a high signal voltage on the IAT sensor signal circuit. As the intake air warm, the sensor resistance becomes lower causing the PCM to monitor a lower voltage. If the PCM detects an excessively high IAT sensor signal voltage, which indicates a low temperature, indicated), DTC P0113 will set.

Conditions for Running The DTC
Conditions for Setting the DTC
Action Taken When the DTC Sets
Conditions for Clearing the MIL/DTC
Diagnostic Aids

If the condition is intermittent, refer to Intermittent Conditions .

If a short to a separate 5-volt source occurs this DTC may set. If this is found to be a problem, a continuity test to all other PCM circuits will be necessary to diagnose the specific circuit.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step verifies that the fault is present.

  2. If DTC P0113 can be repeated only by duplicating the Failure Records conditions, use the Temperature vs. Resistance table in order to test the IAT sensor at various temperatures in order to evaluate the possibility of a shifted sensor that may be open above or below a certain temperature. If this is the case, replace the IAT sensor. Refer to IAT sensor replacement. If the IAT sensor appears OK, the fault is intermittent.

  3. Use a fused jumper during this test. If the IAT signal circuit is shorted to battery or ignition positive voltage the fuse in the jumper will open, indicating a short in the signal circuit.

  4. The new PCM must be programmed.

DTC P0113 - IAT Sensor Circuit High Voltage

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the IAT parameter.

Does the parameter measure less than the specified value?

37°C (34°F)

Go to Step 4

Go to Step 3

3
  1. With a scan tool, review and record Failure Records.
  2. Operate vehicle within Failure Records conditions as noted.

Does the DTC reset?

--

Go to Step 4

Go to Diagnostic Aids

4
  1. Turn OFF the ignition.
  2. Disconnect the IAT Sensor.
  3. Connect a 3-amp fused jumper between the signal circuit of the IAT sensor and the low reference circuit of the IAT sensor at the harness connector.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, observe the IAT parameter.

Does the parameter measure more than the specified value?

135°C (275°F)

Go to Step 6

Go to Step 5

5
  1. Jumper the IAT signal circuit to a good ground.
  2. With a scan tool, observe the IAT parameter.

Does the parameter measure more than the specified value?

135°C (275°F)

Go to Step 7

Go to Step 8

6

Test the signal circuit of the IAT sensor for a short to voltage. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find, and correct the condition?

--

Go to Step 13

Go to Step 10

7

Test the low reference circuit of the IAT sensor for high resistance or an open. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find, and correct the condition?

--

Go to Step 13

Go to Step 9

8

Test the signal circuit of the IAT sensor for an open.

If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find, and correct the condition?

--

Go to Step 13

Go to Step 9

9

Inspect for faulty IAT sensor low reference or signal circuit connections at the PCM. Refer to Testing for Intermittent and Poor Connections in Wiring Systems.

If a problem is found, repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find, and correct the condition?

--

Go to Step 13

Go to Step 12

10

Inspect for faulty connections at the IAT sensor. Refer to Testing for Intermittent and Poor Connections in Wiring Systems.

If a problem is found, repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find, and correct the condition?

--

Go to Step 13

Go to Step 11

11

Replace the IAT sensor. Refer to Intake Air Temperature (IAT) Sensor Replacement .

Did you complete the replacement?

--

Go to Step 13

--

12

Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .

Did you complete the replacement?

--

Go to Step 13

--

13
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run, and pass?

--

Go to Sep 14

Go to Step 2

14

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK