Mitsubishi 380. Manual - part 506

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-116

DTC P0112: Intake Air Temperature Circuit Low Input.

CAUTION

If DTC P0112 has been set, TCL related DTC 
U1120 is also set. After P0112 has been diag-
nosed, don't forget to erase DTC U1120.

.

CIRCUIT OPERATION

• Approximately 5 volts are applied to the intake air 

temperature sensor output terminal (terminal No. 
1) from the ENGINE-ECU (terminal No. 58) via 
the resistor in the ENGINE-ECU. The ground ter-
minal (terminal No. 3) is grounded with 
ENGINE-ECU (terminal No. 26).

• 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 is contained 

within the Mass Airflow Sensor assembly and 
converts the intake air temperature to a voltage.

• The ENGINE-ECU checks whether this voltage is 

within a specified range.

.

DTC SET CONDITIONS

Check Conditions

• None

Judgement Criteria

• Intake air temperature is below -38.3 degreeC for 

2 seconds.

• MIL is activated after 2 Drive cycles.

• No limp home mode.

.

EOBD DRIVE CYCLE PATTERN

Refer to Diagnostic Function 

− EOBD Drive Cycle − 

P.13A-11

.

.

TROUBLESHOOTING HINTS (The most 
likely causes for this code to be set are:)

• Intake air temperature sensor failed.

• Shorted intake air temperature sensor circuit, or 

connector damage.

• Refer to component locations GROUP-

70

• Refer to configuration diagrams GROUP-

80

• Refer to circuit diagrams GROUP-

90

DIAGNOSIS

Required Special Tool:

• : Diagnostic Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

CONNECTOR: B-10

B-10 (GR)

MASS

AIRFLOW

SENSOR

03DB217A

AK303013

CONNECTORS: B-21, B-22

PCM

AB

AIR CLEANER

B-22 (B)

B-21 (B)

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-117

STEP 1. Using diagnostic tool , check data list item 5: 
Intake Air Temperature Sensor.

CAUTION

To prevent damage to diagnostic tool , always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
(1) Connect diagnostic tool  to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Set diagnostic tool  to the data reading mode for item 5, 

Intake Air Temperature Sensor.

• The actual intake air temperature and temperature 

shown with the diagnostic 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 GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

− How to 

Cope with Intermittent Malfunctions 

P.00-14

.

NO :  Go to Step 2.

STEP 2. Check harness connector B-10 at the intake air 
temperature sensor for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 6.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

CONNECTOR: B-10

B-10 (GR)

03DB218A

HARNESS

CONNECTOR:

COMPONENT SIDE

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-118

STEP 3. Check the intake air temperature sensor.
(1) Disconnect the intake air temperature sensor connector 

B-10.

(2) Measure the resistance between intake air temperature 

sensor side connector terminal No. 1 and No. 3.

• There should be continuity. (0.30 − 16 kΩ)

Q: Is the measured resistance between 0.30 and 16 k

Ω?

YES : Go to Step 4.
NO :  Replace the Mass Airflow Sensor assembly. Then go 

to Step 6.

STEP 4. Check for short circuit to ground between intake 
air temperature sensor connector B-10 (terminal No. 1) and 
ENGINE-ECU connector B-20 (terminal No. 58).
Q: Is the harness wire in good condition?

YES : Go to Step 5.
NO :  Repair it. Then go to Step 6.

CONNECTOR: B-10

B-10 (GR)

03DB218A

HARNESS

CONNECTOR:

COMPONENT SIDE

03DB158A

INTAKE AIR TEMPERATURE

SENSOR CONNECTOR

CONNECTOR: B-10

B-10 (GR)

03DB218A

HARNESS

CONNECTOR:

COMPONENT SIDE

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER

MULTIPOINT FUEL INJECTION (MPI) DIAGNOSIS

MULTIPOINT FUEL INJECTION (MPI)

13A-119

STEP 5. Check harness connector B-20 at ENGINE-ECU for 
damage.
Q: Is the harness connector in good condition?

YES : Then go to Step 6.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 6.

STEP 6. Test the EOBD drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− EOBD Drive Cycle − 

P.13A-11

.

(2) Check the diagnostic trouble code (DTC).

Q: Is DTC P0112 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

16DB400A

COVER

ENGINE

CONTROL

UNIT

AIR

CLEANER