DTC P0112:00

IAT sensor No.1 circuit low input

DETECTION CONDITION

• The PCM monitors the IAT sensor No.1 signal. If the PCM detects that the IAT sensor No.1 voltage at the PCM terminal 2U is below 0.19 V for 5 s, the PCM determines that the IAT sensor No.1 circuit has a malfunction.

Diagnostic support note

• This is a continuous monitor (CCM).

• The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle.

• FREEZE FRAME DATA/Snapshot data is available.

• DTC is stored in the PCM memory.

FAIL-SAFE FUNCTION

• Fixes the intake air temperature (for engine control) at 20 °C {68 °F}.

• Inhibits the fuel cut control during shift change.

POSSIBLE CAUSE

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

• IAT sensor No.1 malfunction

• PCM connector or terminals malfunction

• Short to ground in wiring harness between MAF sensor/IAT sensor No.1 terminal A and PCM terminal 2U

• IAT sensor No.1 signal circuit and ground circuit are shorted to each other

• PCM malfunction

STEP

INSPECTION

ACTION

1

NOTE:

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

• Record the FREEZE FRAME DATA/snapshot data on the repair order.

—

Go to the next step.

2

• Verify related Service Bulletins and/or on-line repair information availability.

• Is any related repair information available?

Yes

Perform repair or diagnosis according to the available repair information.

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

No

Go to the next step.

3

• Switch the ignition off.

• Disconnect the MAF sensor/IAT sensor No.1 connector.

• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).

• Is there any malfunction?

Yes

Repair or replace the connector and/or terminals, then go to Step 8.

No

Go to the next step.

4

• Inspect the IAT sensor No.1.

  (See INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION [SKYACTIV-G 2.0].)

• Is there any malfunction?

Yes

Replace the MAF sensor/IAT sensor No.1, then go to Step 8.

(See MASS AIR FLOW (MAF) SENSOR/INTAKE AIR TEMPERATURE (IAT) SENSOR NO.1 REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

No

Go to the next step.

5

• Disconnect the PCM connector.

• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).

• Is there any malfunction?

Yes

Repair or replace the connector and/or terminals, then go to Step 8.

No

Go to the next step.

6

• Verify that the MAF sensor/IAT sensor No.1 and PCM connectors are disconnected.

• Inspect for continuity between MAF sensor/IAT sensor No.1 terminal A (wiring harness-side) and body ground.

• Is there continuity?

Yes

Refer to the wiring diagram and verify whether or not there is a common connector between MAF sensor/IAT sensor No.1 terminal A and PCM terminal 2U.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to ground.

Go to Step 8.

No

Go to the next step.

7

• Verify that the MAF sensor/IAT sensor No.1 and PCM connectors are disconnected.

• Inspect for continuity between MAF sensor/IAT sensor No.1 terminals A and B (wiring harness-side).

• Is there continuity?

Yes

Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:

• MAF sensor/IAT sensor No.1 terminal A—PCM terminal 2U

• MAF sensor/IAT sensor No.1 terminal B—PCM terminal 2AY

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to each other.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to each other.

Go to the next step.

No

Go to the next step.

8

• Always reconnect all disconnected connectors.

• Clear the DTC from the PCM memory using the M-MDS.

  (See AFTER REPAIR PROCEDURE [PCM (SKYACTIV-G 2.0)].)

• Perform the KOEO or KOER self test.

  (See KOEO/KOER SELF TEST [PCM (SKYACTIV-G 2.0)].)

• Is the same DTC present?

Yes

Repeat the inspection from Step 1.

• If the malfunction recurs, replace the PCM.

  (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

Go to the next step.

No

Go to the next step.

9

• Perform the “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [PCM (SKYACTIV-G 2.0)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [PCM (SKYACTIV-G 2.0)].)

No

DTC troubleshooting completed.