Test Procedure
- DC1 PRELIMINARY DIAGNOSIS NOTE: Diagnose any circuit DTCs before range or performance DTCs.
Is DTC P0101, P0102, P0103, P0104, P1100 or P1101 present?
Yes No GO to DC2 . For symptoms without DTCs, GO to DC2 .
For all others, RETURN to ENGINE CONTROLS - SYMPTOM CHARTS (HYBRID) for further direction. - DC2 CHECK THE INTAKE AIR SYSTEM FOR LEAKS, OBSTRUCTIONS AND DAMAGE
- Ignition OFF.
- Check the intake air system (air cleaner, housing, and tubes) for obstructions or blockage.
- Check for broken or loose air outlet tube clamps, cracks or holes in the air outlet tube.
- Check for worn gaskets between the MAF/IAT sensor and the air cleaner assembly.
- Check that the MAF/IAT sensor connector is seated correctly.
- Check the electronic throttle body (ETB) bore for sludge.
- Check the positive crankcase ventilation (PCV) system for leaks and restrictions.
Is a concern present?
Yes No REPAIR as necessary.
Clear the PCM DTCs. REPEAT the self-test.GO to DC3 . - DC3 CHECK FOR VOLTAGE AT THE SENSOR
- Ignition OFF.
- MAF/IAT Sensor connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) MAF/IAT Sensor Connector, Harness Side (-) VPWR - Pin 3 Ground
Is the voltage greater than 10.5 V?
Yes No GO to DC4 . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - DC4 CHECK FOR AN OPEN
- Ignition OFF.
- PCM connector disconnected.
- Measure the resistance between:
(+) MAF/IAT Sensor Connector, Harness Side (-) PCM Connector, Harness Side MAF - Pin 5 MAF - Pin E13 SIGRTN - Pin 4 SIGRTN - Pin E1
Are the resistances less than 5 ohms?
Yes No GO to DC5 . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - DC5 CHECK FOR A SHORT TO GROUND
Is the resistance greater than 10K ohms?
Yes No GO to DC6 . REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. - DC6 CHECK FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) MAF/IAT Sensor Connector, Harness Side (-) MAF - Pin 5 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to DC7 . - DC7 INTERMITTENT CHECK
- Ignition OFF.
- MAF/IAT Sensor connector connected.
- PCM connector connected.
- Access the PCM and monitor the MAF_HZ (FREQ) 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 MAF/IAT sensor and wiggle the harness connector to simulate road shock.
Does the MAF_HZ PID reading change?
Yes No CLEAN the MAF/IAT sensor using CRC Mass Air Flow Sensor Cleaner 05110 or equivalent.
RESET the keep alive memory (KAM), REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .
REPEAT the self-test.
If the concern or DTC is still present, INSTALL a new MAF/IAT sensor. REFER to the Electronic Engine Controls article.
RESET the keep alive memory (KAM), REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .
Clear the PCM DTCs. REPEAT the self-test.GO to DC8 . - DC8 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.