Test Procedure

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2005 Ford RV Cutaway, 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.

F1 PRELIMINARY DIAGNOSIS FOR DTCs P0112 OR P0113

Carry out a visual inspection.
Retrieve and record any continuous and on-demand DTCs.
Record the freeze frame data.
Clear all the DTCs.
Carry out the on-demand self-test.

Are DTCs P0112 or P0113 present?

Yes	No
For P0112, GO to F2. For P0113, GO to F4.	UNABLE to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the fault. REPAIR as necessary. REFER to SYMPTOM CHARTS - 6.0L DIESEL if a driveability concern exists.

F2 DIAGNOSTIC TROUBLE CODE (DTC) P0112

Possible causes:
- signal circuit shorted to ground
- IAT sensor
- PCM
Simulate opposite DTC.
Key OFF.
Disconnect the IAT sensor.
Key ON, engine OFF.
Carry out the on-demand self-test.

Is DTC P0113 present?

Yes	No
INSTALL a new IAT sensor. CLEAR the DTCs. REPEAT the self-test.	GO to F3.

F3 CHECK THE SIGNAL CIRCUIT FOR A SHORT TO GROUND

Key OFF.
Disconnect the PCM body harness connector.
Measure the resistance between the IAT sensor signal circuit pin 6 (F-Super Duty/Excursion with MAF sensor) or pin 2 (F-Super Duty/Excursion without MAF sensor) or pin 1 (E-Series), harness side and ground.

Is the resistance greater than 10,000 ohms?

Yes	No
INSTALL a new PCM. CLEAR the DTCs. REPEAT the self-test.	REPAIR the short to ground in the IAT signal circuit. CLEAR the DTCs. REPEAT the self-test.

F4 DIAGNOSTIC TROUBLE CODE P0113

Possible Causes:
- signal circuit open or shorted to voltage
- signal return circuit open
- IAT sensor
- PCM
Key OFF.
Disconnect the IAT sensor.
Connect a 5-amp fused jumper wire between the following pins:

Vehicle	Circuit	Pin	Circuit	Pin
F-Super Duty / Excursion with MAF sensor	IAT sensor signal	6	IAT sensor signal return	1
F-Super Duty / Excursion without MAF sensor	IAT sensor signal	2	IAT sensor signal return	1
E-Series	IAT sensor signal	1	IAT sensor signal return	2

Key ON, engine OFF.
Carry out the on-demand self-test.

Is DTC P0112 present?

Yes	No
INSTALL a new IAT sensor. CLEAR the DTCs. REPEAT the self-test.	GO to F5.

F5 CHECK THE SIGNAL CIRCUIT FOR AN OPEN

Disconnect the PCM body harness electrical connector.
Key OFF.
Measure the resistance between the PCM body harness connector pin 43, harness side and the IAT sensor signal circuit pin 6 (F-Super Duty/Excursion with MAF sensor) or pin 2 (F-Super Duty/Excursion without MAF sensor) or pin 1 (E-Series), harness side.

Is the resistance less than 5 ohms?

Yes	No
GO to F6.	REPAIR the open in the IAT signal circuit. CLEAR the DTCs. REPEAT the self-test.

F6 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN

Measure the resistance between IAT sensor signal return circuit pin 1 (F-Super Duty/Excursion with MAF sensor) or pin 1 (F-Super Duty/Excursion without MAF sensor) or pin 2 (E-Series), harness side and the PCM body harness connector pin 33, harness side.

Is the resistance less than 5 ohms?

Yes	No
GO to F7.	REPAIR the open in the IAT sensor signal return circuit. CLEAR the DTCs. REPEAT the self-test.

F7 CHECK THE SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE

Key ON, engine OFF.
Measure the voltage between the IAT sensor signal circuit pin 6 (F-Super Duty/Excursion with MAF sensor) pin 1 (F-Super Duty/Excursion without MAF sensor) or pin 1 (E-Series), harness side and ground.

Is any voltage indicated?

Yes	No
REPAIR the short in the IAT signal circuit. CLEAR the DTCs. REPEAT the self-test.	INSTALL a new PCM. CLEAR the DTCs. REPEAT the self-test.