Page 1 of 5 Year = 2011 Model = Mustang Engine = 5.0L VIN = IDS Version = t Available Intake Air Temperature (IAT) Sensor This pinpoint test is intended to diagnose the following: IAT sensor (12A697) integrated mass air flow/intake air temperature ( MAF/IAT) sensor (12B579) harness circuits: IAT and SIGRTN powertrain control module (PCM) (12A650)
Page 2 of 5 IAT Sensor Connector Harness Side Circuit Pin SIGRTN (Signal Return) 4 IAT (Intake Air Temperature) 2 VPWR (Vehicle Power) 3 MAF (Mass Air Flow) 5 PCM Connector - For PCM connector views or reference values, refer to Section 6. Harness Side Circuit IAT (Intake Air Temperature) SIGRTN (Signal Return) Pin B47 B2 DA1 : PRELIMINARY DIAGNOSIS Are DTCs P009A, P0111, P0112, P0113, P0114, or P1112 present? For DTCs P009A, P0111, P0112, P0113, P0114 or P1112, Go to DA2. For all others, GO to Section 4, Diagnostic Trouble Code (DTC) Charts and Descriptions. For symptoms without DTCs, Go to DA2.
Page 3 of 5 the MAF/IAT sensor to determine which circuits to measure Ignition OFF. IAT Sensor connector disconnected. PCM connector disconnected. Ground PCM Connector, Harness Side IAT - Pin B47 SIGRTN - Pin B2 MAF RTN Is the resistance less than 5 Ohm? Go to DA3. REPAIR the open circuit. DA3 : CHECK FOR A SHORT BETWEEN CIRCUITS IN THE HARNESS Ground VPWR - Pin 3 MAF RTN MAF - Pin 5 Are the resistances greater than 10K ohms? Go to DA4. REPAIR the short circuit.
Page 4 of 5 REPAIR the short circuit. Go to DA5. DA5 : INTERMITTENT CHECK Ignition OFF. PCM connector connected. IAT Sensor connector connected. Ignition ON, engine OFF. Access the PCM and monitor the IAT (VOLT) PID. While observing the PID, wiggle, shake, and bend small sections of the wiring harness working from the sensor to the PCM Lightly tap on the IAT sensor and wiggle the harness connector to simulate road shock. Does the IAT PID reading change? REPAIR as necessary or INSTALL a new IAT sensor. REFER to the Workshop Manual Section 303-14, Electronic Engine Controls. RESET the keep alive memory ( KAM). REFER to Section 2, Resetting The Keep Alive Memory (KAM). Go to DA6. DA6 : INTAKE AIR TEMPERATURE ( IAT ) SENSOR AMBIENT AIR TEMPERATURE ( AAT) SENSOR CORRELATION NOTE: Check temperature values while engine is at ambient temperature, cold soak the engine for a minimum of 8 hours while not in direct sun light, if necessary. Ignition ON, engine OFF. Access the PCM and monitor the IAT (TEMP) PID. For Fiesta, Access the PCM and monitor the OUTDR_TMP (TEMP) PID. For all others, Access the PCM and monitor the AAT (TEMP) PID. Are the temperature readings within 18ºC (32.4ºF) of each other? Go to DA7. INSTALL a new IAT sensor. REFER to the Workshop Manual Section 303-14, Electronic Engine Controls. RESET the keep alive memory ( KAM). REFER to Section 2, Resetting The Keep Alive Memory (KAM).
Page 5 of 5 Connect a 5 amp fused jumper wire between the following: Point A Point B Record the IAT PID value Does the IAT PID change from greater than 3.0 volts to less than 0.20 volt when the jumper is connected? INSTALL a new IAT sensor. REFER to the Workshop Manual Section 303-14, Electronic Engine Controls. RESET the keep alive memory ( KAM). REFER to Section 2, Resetting The Keep Alive Memory (KAM). Go to DA8. DA8 : 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? INSTALL a new PCM. The system is operating correctly at this time. The REFER to Section 2, Flash Electrically Erasable concern may have been caused by a loose or Programmable Read Only Memory (EEPROM), corroded connector. Programming the VID Block for a Replacement PCM.