P0111
DTC P0111: Intake Air Temperature Circuit Range/Performance ProblemIntake Air Temperature Sensor Circuit:
CIRCUIT OPERATION
- Approximately 5 volts are applied to the intake air temperature sensor output terminal (terminal No.6) from the ECM (terminal No.62) via the resistor in the ECM. The ground terminal (terminal No.5) is grounded with ECM (terminal No.34).
- 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 checks whether this voltage is within a specified range.
DESCRIPTIONS OF MONITOR METHODS
- Intake air temperature sensor output voltage does not change when specified go/stop operations are repeated.
MONITOR EXECUTION
- Continuous
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Not applicable
Sensor (The sensor below is determined to be normal)
- Not applicable
DTC SET CONDITIONS
Logic Flow Chart:
Logic Flow Chart
Check Conditions
- Engine coolant temperature is higher than 76 degrees C (169 degrees F).
- Repeat 2 or more times: drive*1, stop*2.
Drive*1: vehicle speed higher than 50 km/h (31 mph) lasting a total of more than 60 seconds.
Stop*2: vehicle speed lower than 1.5 km/h (1 mph) lasting more than 30 seconds.
Judgment Criterion
- Changes in the intake air temperature is lower than 1 degree C (34 degrees F).
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 8. OBD-II Drive Cycle Pattern Lists
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Intake air temperature sensor failed.
- Open intake air temperature sensor circuit, harness damage, or connector damage.
- ECM failed.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B
STEP 1. Using scan tool MB991958, check data list item 13: Intake Air Temperature Sensor.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Remove the air intake hose from the volume airflow sensor.
3. Turn the ignition switch to the "ON" position.
4. Set scan tool MB991958 to the data reading mode for item 13, Intake Air Temperature Sensor.
5. Heat the sensor using a hair dryer.
- The indicated temperature increases.
NOTE: Do not allow it to increase over 80 degrees C (176 degrees F).
6. Turn the ignition switch to the "LOCK" (OFF) position.
7. Attach the air intake hose.
Q: Is the sensor operating properly?
YES: It can be assumed that this malfunction is intermittent.
NO: Go to Step 2.
STEP 2. 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 terminals No.5 and No.6.
3. Measure resistance while heating the sensor using a hair drier.
Standard value:
13 - 17 kOhms [at -20 degrees C (-4 degrees F)]
5.3 - 6.7 kOhms [at 0 degree C (32 degrees F)]
2.3 - 3.0 kOhms [at 20 degrees C (68 degrees F)]
1.0 - 1.5 kOhms [at 40 degrees C (104 degrees F)]
0.56 - 0.76 kOhm [at 60 degrees C (140 degrees F)]
0.30 - 0.42 kOhm [at 80 degrees C (176 degrees F)]
Q: Is the measured resistance at the standard value?
YES: Go to Step 3.
NO: Replace the volume airflow sensor. Then go to Step 9.
STEP 3. Check harness connector B-105 at the intake air temperature sensor for damage.
Q: Is the harness connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it. Then go to Step 9.
STEP 4. Check for continuity at intake air temperature sensor harness side connector B-105.
1. Disconnect connector B-105 and measure at the harness side.
2. Check for the continuity between terminal No.5 and ground.
- Should be less than 2 Ohms.
Q: Does continuity exist?
YES: Go to Step 7.
NO: Go to Step 5.
STEP 5. Check harness connector C-121 at ECM for damage.
Q: Is the harness connector in good condition?
YES: Go to Step 6.
NO: Repair or replace it. Then go to Step 9.
STEP 6. Check for open circuit and harness damage between intake air temperature sensor connector B-105 (terminal No.5) and ECM connector C-121 (terminal No.34).
Q: Is the harness wire in good condition?
YES: Replace the ECM. Then go to Step 9.
NO: Repair it. Then go to Step 9.
STEP 7. Check harness connector C-119 at ECM for damage.
Q: Is the harness connector in good condition?
YES: Go to Step 8.
NO: Repair or replace it. Then go to Step 9
STEP 8. Check for open circuit and harness damage between intake air temperature sensor connector B-105 (terminal No.6) and ECM connector C-119 (terminal No.62).
Q: Is the harness wire in good condition?
YES: Replace the ECM. Then go to Step 9.
NO: Repair it. Then go to Step 9.
STEP 9. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to, Diagnostic Function - OBD-II Drive Cycle - Pattern 8. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).
Q: Is DTC P0111 set?
YES: Retry the troubleshooting.
NO: The inspection is complete.