Test Procedure
WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
- FA1 PRELIMINARY DIAGNOSIS NOTE: Diagnose circuit DTCs before range or performance DTCs.
Are DTCs P0070, P0071, P0072 or P0073 present?
Yes No GO to FA2 . RETURN to ENGINE CONTROLS - SYMPTOM CHARTS (DIESEL) , Symptom Charts for further direction. - FA2 CHECK FOR AN OPEN
- Ignition OFF.
- AAT Sensor connector disconnected.
- PCM-B connector disconnected.
- Measure the resistance between:
(+) AAT Sensor Connector, Harness Side (-) PCM-B Connector, Harness Side AAT - Pin 1 AAT - Pin 3 SIGRTN - Pin 2 SIGRTN - Pin 44
Are the resistances less than 5 ohms?
Yes No GO to FA3 . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - FA3 CHECK FOR A SHORT TO GROUND
- Measure the resistance between:
(+) AAT Sensor Connector, Harness Side (-) AAT - Pin 1 Ground - Measure the resistance between:
(+) AAT Sensor Connector, Harness Side (-) AAT Sensor Connector, Harness Side AAT - Pin 1 SIGRTN - Pin 2
Is the resistance greater than 10K ohms?
Yes No GO to FA4 . REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- FA4 CHECK FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) AAT Sensor Connector, Harness Side (-) AAT - Pin 1 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to FA5 . - FA5 INTERMITTENT CHECK
- Ignition OFF.
- AAT Sensor connector connected.
- PCM-B connector connected.
- Ignition ON, engine OFF.
- Access the PCM and monitor the AAT_V (VOLT) PID.
- While observing the PID, carry out the following:
- Wiggle all accessible harness from the AAT sensor to the PCM and lightly tap on the sensor.
- Wiggle the AAT sensor connector.
- Look for sudden changes in the voltage when the harness and connector are wiggled or when the AAT sensor is tapped.
Is a concern present?
Yes No REPAIR as necessary.
Clear the PCM DTCs. REPEAT the self-test.GO to FA6 . - FA6 TEMPERATURE SENSOR CORRELATION NOTE: Check temperature values while engine is at ambient temperature, cold soak the engine for a minimum of 8 hours if necessary.
- Ignition ON, engine OFF.
- Access the PCM and monitor the AAT (TEMP), CAC_T (TEMP), IAT11 (TEMP), ECT2 (TEMP) and EGRT11 (TEMP) PIDs.
- The AAT temperature must be within the following ranges:
- Within 10°C (18°F) degrees of the CAC_T reading
- Within 15°C (27°F) degrees of the IAT11 reading
- Within 20°C (36°F) degrees of the ECT2 reading
- Within 16°C (28.8°F) degrees of the EGRT11 reading
Is the AAT PID within specification?
Yes No Unable to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the concern. REPAIR as necessary. INSTALL a new AAT sensor. REFER to the appropriate Climate Control article. Clear the PCM DTCs. REPEAT the self-test. If the concern or DTC is still present,
GO to FA7 . - FA7 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test.
- Verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.