ECD SYSTEM, Diagnostic DTC:P0111, P0112, P0113

DTC Code	DTC Name
P0111	Intake Air Temperature Sensor Gradient Too High
P0112	Short to GND in Intake Air Temperature Sensor Circuit
P0113	Open or Short to B+ in Intake Air Temperature Sensor Circuit

DESCRIPTION

Located between the air cleaner filter and the turbocharger, the mass air flow meter measures the mass of intake air flowing into the engine.

The MAF also measures the temperature of the air flowing into the engine.

The intake air temperature sensor in the air flow meter is composed of an NTC (Negative Temperature Coefficient) type thermistor.

Based on this information, the ECM:

Calculates the theoretical air volume.
Calculates the injection advance.
Calculates the injection flow.

Triggers additional heating.

CAUTION:

Do not touch the hot film because it is easily broken.

DTC No.	DTC Detection Condition	Trouble Area	Possible to Detect
DTC No.	DTC Detection Condition	Trouble Area	Ignition Switch	Engine Run
P0111	The output from the intake air temperature sensor suddenly changes for 1.5 sec. or more. (3 trip detection logic)	Mass air flow meter Mass air flow meter circuit ECM	ON	ON
P0112	Mass air flow meter (intake air temperature) sensor output is more than 130°C (266°F) (less than 0.18 V) for 10 sec. or more. (3 trip detection logic)	Mass air flow meter Mass air flow meter circuit ECM	ON	ON
P0113	Mass air flow meter (intake temperature) sensor output is less than -40°C (-40°F) (more than 4.78 V) for 10 sec. or more. (3 trip detection logic)	Mass air flow meter Mass air flow meter circuit ECM	ON	ON

FAIL-SAFE

DTC No.	Fail-safe Operation	Fail-safe Deactivation Condition
P0111	A value of 40°C (104°F) is used as the intake air temperature.	Normal condition is restored.
P0112	A value of 40°C (104°F) is used as the intake air temperature.	Normal condition is restored.
P0113	A value of 40°C (104°F) is used as the intake air temperature.	Normal condition is restored.

WIRING DIAGRAM

INSPECTION PROCEDURE

Tech Tips

When DTC P0111, P0112 or P0113 is detected, check the intake air temperature by selecting the following menu items on the intelligent tester: Powertrain / Engine and ECT / Data List / Intake Air Temp.

Displayed (Temperature)	Malfunction
Less than -40°C (-40°F)	Open or short to +B circuit
More than 130°C (266°F)	Short to ground

If the ECM is replaced, variant coding (variant coding indicates the presence of vehicle accessory items, A/C, etc.) should always be performed Click here.
Before removing the ECM and the peripheral parts, wait at least 3 minute after turning the ignition switch off (If the cooling fan is operating, remove the ECM and the peripheral parts after the fan stops.).

PROCEDURE

READ VALUE OF INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

Warm up the engine.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position and turn the intelligent tester on.
Select the following menu items: Powertrain / Engine and ECT / Intake Air Temp.

Read the value.

OK
The displayed temperature is the same as the actual intake air temperature, and the sensor output does not fluctuate significantly.

Tech Tips

If there is an open circuit, the intelligent tester indicates less than -40°C (-40°F).
If there is a short circuit to ground, the intelligent tester indicates more than 130°C (266°F).

CHECK MASS AIR FLOW METER (INTAKE AIR TEMPERATURE SENSOR) Click here

CHECK FOR INTERMITTENT PROBLEMS

CHECK MASS AIR FLOW METER (INTAKE AIR TEMPERATURE SENSOR)

Disconnect the B40 mass air flow meter connector.

Measure the resistance according to the value(s) in the table below.

Standard resistance

Tester Connection	Specified Condition
2 - 3	The resistance value is within the acceptable range shown in the illustration.

REPLACE MASS AIR FLOW METER (INTAKE AIR TEMPERATURE SENSOR)

INSPECT ECM (VOLTAGE)

Disconnect the B40 mass air flow meter connector.
Turn the ignition switch to the ON position.

Measure the voltage according to the value(s) in the table below.

Standard voltage

Tester Connection	Specified Condition
Mass air flow meter (B40-2) - Body ground	4.7 to 5.3 V

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) Click here

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - BODY GROUND)

Disconnect the B40 mass air flow meter connector.

Measure the resistance according to the value(s) in the table below.

Standard resistance

Tester Connection	Specified Condition
Mass air flow meter (B40-3) - Body ground	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE MASS AIR FLOW METER

NEXT

READ VALUE OF INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

Warm up the engine.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position and turn the intelligent tester on.
Select the following menu items: Powertrain / Engine and ECT / Intake Air Temp.

Read the value.

OK
The displayed temperature is the same as the actual intake air temperature, and the sensor output does not fluctuate significantly.

Tech Tips

If there is an open circuit, the intelligent tester indicates less than -40°C (-40°F).
If there is a short circuit to ground, the intelligent tester indicates more than 130°C (266°F).

REPLACE ECM

END

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

Disconnect the B54 ECM connector.
Disconnect the B40 mass air flow meter connector.

Measure the resistance according to the value(s) in the table below.

Standard resistance

Check for open

Tester Connection	Specified Condition
EVG (B54-8) - Mass air flow meter (B40-2)	Below 1 Ω

Check for short

Tester Connection	Specified Condition
EVG (B54-8) or Mass air flow meter (B40-2) - Body ground	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK POWER SOURCE CIRCUIT
1. Check that the battery voltage, ECM power source voltage, and the ground condition of the ECM are normal.
  
  OK
  
  The battery voltage, ECM power source voltage, and the ground condition of the ECM are normal.
  
  Tech Tips
  
  Make sure that the battery is not discharged during the inspection.
NG
REPAIR POWER SOURCE CIRCUIT

OK

REPLACE ECM