DTC P0112

IAT sensor circuit low input

DETECTION CONDITION

• The PCM monitors the IAT sensor signal. If the PCM detects that the IAT sensor voltage is below 0.16 V, the PCM determines that the IAT sensor circuit has a malfunction.

Diagnostic support note

• This is a continuous monitor (CCM).

• The MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.

• PENDING CODE is available if the PCM detects the above malfunction condition.

• FREEZE FRAME DATA is available.

• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• IAT sensor malfunction

• Connector or terminal malfunction

• Short to ground in wiring harness between MAF/IAT sensor terminal D and PCM terminal 1AT

• IAT sensor signal circuit and IAT sensor ground circuit are shorted each other

• PCM malfunction

STEP

INSPECTION

ACTION

1

• Has FREEZE FRAME DATA been recorded?

Yes

Go to the next step.

No

Record the FREEZE FRAME DATA on the repair order, then 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

• Turn the ignition switch off.

• Disconnect the MAF/IAT sensor connector.

• Inspect for bent terminal of MAF/IAT sensor terminals D and E (part-side).

• Is there any malfunction?

Yes

Repair or replace the terminal, then go to Step 7.

No

Go to the next step.

4

• Connect the M-MDS to DLC-2.

• Access IAT PID.

• Verify IAT value when disconnecting the MAF/IAT sensor connector.

• Does IAT value change?

Yes

Replace the MAF/IAT sensor, then go to Step 7.

(See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

5

• Turn the ignition switch off.

• Disconnect the PCM connector.

• Inspect for continuity between MAF/IAT sensor terminal D (wiring harness-side) and body ground.

• Is there continuity?

Yes

Repair or replace the wiring harness for a short to ground, then go to Step 7.

No

Go to the next step.

6

• Inspect for continuity between MAF/IAT sensor terminals D and E (wiring harness-side).

• Is there continuity?

Yes

Repair or replace the wiring harness for a short, then go to Step 7.

No

Go to the next step.

7

• Make sure to reconnect all disconnected connectors.

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

• Start the engine.

• Is same DTC present?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

8

• Perform the “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [LF].)

• Are any DTC present?

Yes

Go to the applicable DTC troubleshooting.

(See DTC TABLE [LF].)

No

Troubleshooting completed.