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DTC P0112:00 [PCM (SKYACTIV-D)]

id0102t5701400

Outline

System malfunction location

IAT sensor No.1 circuit low input

Detection condition

•  With the following conditions met, the IAT sensor No.1 voltage is less than 0.12 V for a continuous 5 s.

―  Battery positive voltage: 8—16 V

―  0.5 s have elapsed after ignition is switched ON (engine off or on)

―  The following DTCs are not detected

•  Constant voltage power supply control system: P0642:00, P0643:00

Fail-safe

•  PCM restricts engine torque.

•  Limits the maximum engine speed.

•  Inhibits the DENOx/DESOx control.

•  Inhibits the diesel particulate filter regeneration control.

•  Inhibits the boost control.

•  Inhibits the EGR control.

•  PCM restricts engine-transaxle integration control. (ATX)

•  Inhibits engine-stop by operating the i-stop function.

Possible cause

•  Intake air temperature is abnormally high

•  MAF/IAT sensor No.1 connector or terminal malfunction

•  IAT sensor No.1 malfunction

•  Short to ground in IAT sensor No.1 signal circuit

•  PCM connector or terminal malfunction

•  Short circuit in IAT sensor No.1 signal circuit and ground circuit

•  PCM malfunction

System malfunction location	IAT sensor No.1 circuit low input
Detection condition	• With the following conditions met, the IAT sensor No.1 voltage is less than 0.12 V for a continuous 5 s. ― Battery positive voltage: 8—16 V ― 0.5 s have elapsed after ignition is switched ON (engine off or on) ― The following DTCs are not detected • Constant voltage power supply control system: P0642:00, P0643:00
Fail-safe	• PCM restricts engine torque. • Limits the maximum engine speed. • Inhibits the DENOx/DESOx control. • Inhibits the diesel particulate filter regeneration control. • Inhibits the boost control. • Inhibits the EGR control. • PCM restricts engine-transaxle integration control. (ATX) • Inhibits engine-stop by operating the i-stop function.
Possible cause	• Intake air temperature is abnormally high • MAF/IAT sensor No.1 connector or terminal malfunction • IAT sensor No.1 malfunction • Short to ground in IAT sensor No.1 signal circuit • PCM connector or terminal malfunction • Short circuit in IAT sensor No.1 signal circuit and ground circuit • PCM malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION

•  Record the freeze frame data/snapshot data.

Note

•  Recording can be facilitated using the screen capture function of the PC.

—

Go to the next step.

2

VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY

•  Verify related Service Bulletins, on-line repair information, or Service Information availability.

•  Is any related Information available?

Yes

Perform repair or diagnosis according to the available information.

•  If the vehicle is not repaired, go to the next step.

No

Go to the next step.

3

INSPECT MAF/IAT SENSOR No.1 CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

4

DETERMINE IF MALFUNCTION IS CAUSED BY IAT SENSOR No.1 MALFUNCTION OR WIRING HARNESS SIDE MALFUNCTION

•  Verify that the MAF/IAT sensor No.1 connector is disconnected.

•  Switch the ignition ON (engine off).

Note

•  Another DTC may be stored by the PCM detecting an open circuit.

•  Measure the voltage at MAF/IAT sensor No.1 terminal A (vehicle wiring harness side).

•  Is the voltage approx. 5 V?

Yes

Replace MAF/IAT sensor No.1, then go to repair completion verification.

(See MASS AIR FLOW (MAF) SENSOR/INTAKE AIR TEMPERATURE (IAT) SENSOR NO.1 REMOVAL/INSTALLATION [SKYACTIV-D 1.8])

No

Go to the next step.

5

INSPECT PCM CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

INSPECT IAT SENSOR No.1 SIGNAL CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

7

INSPECT IAT SENSOR No.1 GROUND CIRCUIT AND SIGNAL CIRCUIT FOR SHORT CIRCUIT

•  Inspect the applicable circuits for a short circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to repair completion verification.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Replicate the vehicle conditions at the time the DTC was detected using the following procedure.

―  Perform the KOEO or KOER self-test.
(See DTC INSPECTION)

•  Perform the DTC inspection for the PCM.
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION • Record the freeze frame data/snapshot data. Note • Recording can be facilitated using the screen capture function of the PC.	—	Go to the next step.
2	VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY • Verify related Service Bulletins, on-line repair information, or Service Information availability. • Is any related Information available?	Yes	Perform repair or diagnosis according to the available information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT MAF/IAT SENSOR No.1 CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	DETERMINE IF MALFUNCTION IS CAUSED BY IAT SENSOR No.1 MALFUNCTION OR WIRING HARNESS SIDE MALFUNCTION • Verify that the MAF/IAT sensor No.1 connector is disconnected. • Switch the ignition ON (engine off). Note • Another DTC may be stored by the PCM detecting an open circuit. • Measure the voltage at MAF/IAT sensor No.1 terminal A (vehicle wiring harness side). • Is the voltage approx. 5 V?	Yes	Replace MAF/IAT sensor No.1, then go to repair completion verification. (See MASS AIR FLOW (MAF) SENSOR/INTAKE AIR TEMPERATURE (IAT) SENSOR NO.1 REMOVAL/INSTALLATION [SKYACTIV-D 1.8])
4		No	Go to the next step.
5	INSPECT PCM CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT IAT SENSOR No.1 SIGNAL CIRCUIT FOR SHORT TO GROUND • Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT IAT SENSOR No.1 GROUND CIRCUIT AND SIGNAL CIRCUIT FOR SHORT CIRCUIT • Inspect the applicable circuits for a short circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to repair completion verification.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Replicate the vehicle conditions at the time the DTC was detected using the following procedure. ― Perform the KOEO or KOER self-test. (See DTC INSPECTION) • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.