FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0113

Intake Air Temperature Sensor Circuit:






CIRCUIT OPERATION
- Approximately 5 volts are applied to the intake air temperature sensor output terminal (terminal 6) from the ECM (terminal 72) or PCM (terminal 64) via the resistor in the ECM or PCM . The ground terminal (terminal 5) is grounded with ECM (terminal 40) or PCM (terminal 16) .
- The intake air temperature sensor is a negative temperature coefficient type of resistor. When the intake air temperature rises, the resistance decreases.
- The intake air temperature sensor output voltage increases when the resistance increases and decreases when the resistance decreases.

TECHNICAL DESCRIPTION
- The intake air temperature sensor converts the intake air temperature to a voltage.
- The ECM or PCM
checks whether this voltage is within a specified range.

DTC SET CONDITIONS

Check Conditions
- 2 seconds or more have passed since the staring sequence was completed.

Judgement Criteria
- Intake air temperature sensor output voltage has continued to be 4.6 volts or higher [corresponding to an air intake temperature of -40 °C (-40 °F) or lower] for 2 seconds.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Intake air temperature sensor failed.
- Open or shorted intake air temperature sensor circuit, or loose connector
- ECM failed.
- PCM failed.


DIAGNOSIS

Required Special Tools
- MB991502: Scan Tool (MUT-II)




STEP 1. Using scan tool MB991502, check data list item 13: Intake Air Temperature Sensor.

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.

1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991502 to the data reading mode for item 13, Intake Air Temperature Sensor.
- The intake air temperature and temperature shown with the scan tool should approximately match.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points.

NO: Go to Step 2.




STEP 2. Check connector B-105 at the intake air temperature sensor for damage.

Q: Is the connector in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.

STEP 3. Check the intake air temperature sensor.




1. Disconnect the intake air temperature sensor connector B-105.




2. Measure the resistance between intake air temperature sensor side connector terminal 5 and 6.
- There should be continuity. (0.30 - 1.0 kohm)

Q: Is the resistance normal?

YES: Go to Step 4.

NO: Replace the volume air flow sensor. Then go to Step 11.




STEP 4. Check the sensor supply voltage at intake air temperature sensor harness side connector B-105.
1. Disconnect the connector B-105 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 6 and ground.
- Voltage should be between 4.5 and 4.9 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES: Go to Step 8.

NO: Go to Step 5.

STEP 5. Check the sensor supply voltage at ECM connector C-115 or PCM connector C-118
by backprobing.
1. Do not disconnect the ECM connector C-115 or PCM connector C-118
.
2. Disconnect the intake air temperature sensor connector B-105.
3. Turn the ignition switch to the "ON" position.







4. Measure the voltage between terminal 72 or 64
and ground by backprobing.
- Voltage should be between 4.5 and 4.9 volts.

5. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES: Go to Step 6.

NO: Go to Step 7.




STEP 6. Check connector C-115 at ECM or connector C-118 at PCM
for damage.

Q: Is the connector in good condition?

YES: Repair harness wire between intake air temperature sensor connector B-105 and ECM connector C-115 or PCM connector C-118
because of open circuit. Then go to Step 11.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.




STEP 7. Check connector C-115 at ECM or connector C-118 at PCM
for damage.

Q: Is the connector in good condition?

YES: Replace the ECM or PCM. Then go to Step 11

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11.

STEP 8. Check the continuity at intake air temperature sensor harness side connector B-105.
1. Disconnect the connector B-105 and measure at the harness side.




2. Check for the continuity between terminal 5 and ground.
- Should be less than 2 ohm.

Q: Is the continuity normal?

YES: Replace the ECM or PCM. Then go to Step 11.

NO: Go to Step 9.




STEP 9. Check connector C-119 at ECM or connector C-120 at PCM
for damage.

Q: Is the connector in good condition?

YES: Go to Step 10.

NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 11







STEP 10. Check for open circuit between intake air temperature sensor connector B-105 and ECM connector C-119 or PCM connector C-120
.

Q: Is the harness wire in good condition?

YES: Replace the ECM or PCM. Then go to Step 11.

NO: Repair it. Then go to Step 11.

STEP 11. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to Procedure 6 Other Monitor.
2. Check the diagnostic trouble code (DTC).

Q: Is the DTC P0113 output?

YES: Retry the troubleshooting.

NO: The inspection is complete.