Nissan Sentra B18 (2020-2025) Service Manual: P0112 Iat Sensor

Nissan Sentra B18 (2020-2025) Service Manual / Engine / Work Procedure (After Replacing Electric Throttle Control Actuator) / Dtc/circuit Diagnosis / P0112 Iat Sensor

Dtc Description

DTC Description

DTC DETECTION LOGIC

DTC	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
P0112	IAT SEN/CIRCUIT-B1 (Intake air temperature sensor 1 circuit low bank 1)	Diagnosis condition	Ignition switch ON
		Signal (terminal)	Intake air temperature sensor signal
		Threshold	An excessively low voltage from the sensor is sent to ECM
		Diagnosis delay time	—

POSSIBLE CAUSE

Harness or connectors (The intake air temperature sensor circuit is open or shorted.)
Intake air temperature sensor

FAIL-SAFE

Engine Control System

Not applicable

Idle Start/Stop System

When a DTC is detected, the start/stop indicator lamp blinks slowly and the idle start/stop system operation is prohibited.

When ECM detects error while operating the idle start/stop system, ECM restarts the engine.

Confirmation Procedure

Confirmation Procedure

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

>>
GO TO 2.
PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >>
Proceed to DTC Diagnosis Procedure.
NO-1 >>
To check malfunction symptom before repair: Refer to Intermittent Incident.
NO-2 >>
Confirmation after repair: INSPECTION END

Dtc Diagnosis Procedure

DTC Diagnosis Procedure

CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR POWER SUPPLY-1

Turn ignition switch OFF.
Disconnect mass air flow (MAF) sensor (intake air temperature sensor is built-in) harness connector.
Turn ignition switch ON.

Check the voltage between MAF sensor harness connector terminals.

MAF sensor	Voltage (Approx.)
F31	1	3	5 V

MAF sensor

Voltage

(Approx.)

Connector

Terminal

F31

5 V

Is the inspection result normal?

YES >>

GO TO 6.

NO >>

GO TO 2.

CHECK IAT SENSOR POWER SUPPLY-2

Check the voltage between MAF sensor harness connector and ground.

+	−	Voltage (Approx.)
F31	1	Ground	5 V

−

Voltage

(Approx.)

MAF sensor

Connector

Terminal

F31

Ground

5 V

Is the inspection result normal?

YES >>

GO TO 4.

NO >>

GO TO 3.

CHECK IAT SENSOR POWER SUPPLY CIRCUIT

Turn ignition switch OFF.
Disconnect ECM harness connector.

Check the continuity between MAF sensor harness connector and ECM harness connector.

MAF sensor		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
F31	1	F24	27	Existed

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES >>

Perform trouble diagnosis for ECM power supply circuit. Refer to Diagnosis Procedure.

NO >>

Repair or replace malfunctioning part.

CHECK IAT SENSOR GROUND CIRCUIT

Turn ignition switch OFF.
Disconnect ECM harness connector.

Check the continuity between MAF sensor harness connector and ECM harness connector.

MAF sensor		ECM		Continuity
Connector	Terminal	Connector	Terminal	Continuity
F31	3	F24	23	Existed

Also check harness for short to power.

Is the inspection result normal?

YES >>

GO TO 5.

NO >>

Repair or replace malfunctioning part.

CHECK ECM GROUND CIRCUIT

Check the continuity between ECM harness connector and ground.

ECM		—	Continuity
Connector	Terminal	—	Continuity
F24	5	Ground	Existed
F24	65
F25	69
E16	157
	159
	162

Also check harness for short to power.

Is the inspection result normal?

YES >>

INSPECTION END

NO >>

Repair or replace malfunctioning part.

CHECK INTAKE AIR TEMPERATURE SENSOR

Refer to Component Inspection.

Is the inspection result normal?
YES >>
INSPECTION END
NO >>
Replace mass air flow (MAF) sensor (intake air temperature sensor is built-in). Refer to Exploded View.

P0111 Iat Sensor

Dtc Description DTC Description DTC DETECTION LOGIC DTC CONSULT screen terms (Trouble ...

Other materials:

P155e Generator Voltage
Dtc Description DTC Description DTC DETECTION LOGIC DTC CONSULT screen terms (Trouble diagnosis content) DTC detection condition ...

Parking Brake Control
Exploded View Exploded View 1. Front parking brake cable 2. Parking brake pedal assembly ...

Additional Service When Replacing Chassis Control Module (with Built in Steering Angle Sensor)
Description Description When replacing the chassis control module, the procedures of BEFORE REPLACEMENT and AFTER REPLACEMENT must be performed. For work procedure, refer to Work Procedure. BEFORE REPLACEMENT When replacing the chassis control module, save “Operation log”. ...