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Mass Air Flow (MAF) Sensor

DTC P0102, P0103, P1100, P1101 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0102, P0103, P1100, P1101 MASS AIR FLOW (MAF) SENSOR
DETECTION CONDITION 
  • P0102 indicates MAF signal went below 0.23 volts sometime during normal engine operation or KOER Self Test.
  • P0103 indicates MAF signal went above 4.60 volts sometime during normal engine operation or KOER Self Test.
  • P1100 indicates MAF signal went below 0.23 volt or above 4.60 volts sometime during the last 40 warm-up cycles.
  • P1101 indicates MAF signal was greater than 0.27 volt during KOEO Self Test or MAF signal was not between 0.46-2.44 volts during KOER Self Test.
POSSIBLE CAUSE 
  • Damaged MAF sensor (P0102, P0103, P1101).
  • Blocked MAF sensor screen (P0103).
  • MAF sensor disconnected (P0102).
  • Contaminated MAF sensor (P1101).
  • MAF sensor circuit concerns:
    • Sensor partially connected (P1101).
    • Open PWR GND harness circuit (P0102, P1101).
    • Open MAF RTN circuit (P0102, P1011).
    • Open VPWR circuit (P0102).
    • MAF SIG circuit shorted to VPWR (P0103).
    • MAF SIG circuit shorted to ground (P0102).
    • MAF SIG circuit open (P0102).
    • Sensor connector or harness with poor continuity (P1100).
    • Sensor harness with intermittent short (P1100).
    • Sensor with internal intermittent open or short (P1100).
  • Damaged PCM (P0102, P0103, P1101).
  • Intake air leak near MAF sensor (P0102).
  • Throttle position (TP) system - possible closed throttle indication (P0102).
HINT  MAF Sensor Description 
  • Measures the amount of air entering the engine.
  • Outputs an analog voltage signal to PCM which uses this information to calculate the required fuel injector pulse width in order to provide the desired air/fuel ratio. This input is also used in determining transmission electronic pressure control (EPC), shift and torque converter clutch scheduling.
G03988108Courtesy of MAZDA MOTORS CORP.
G03988109Courtesy of MAZDA MOTORS CORP.
G03988110Courtesy of MAZDA MOTORS CORP.
DTC P0102, P0103, P1100, P1101 INSPECTION

STEP INSPECTION ACTION
1
  • Was PCM Quick Test performed? 
 Yes For KOER DTC P1101:
Go to step 2.
For KOEO DTC P1101:
Go to step 4.
For Continuous Memory DTC P1100:
Go to step 12.
For DTC P0102:
Go to step 3.
For DTC P0103:
Go to step 14.
No Perform PCM Quick Test.
2 DTC P1101: CHECK FOR MAF SENSOR CONTINUOUS MEMORY DTCs
  • Clear DTC using NGS Tester Generic OBDII function.
  • Drive vehicle for 6 to 10 minutes.
  • Retrieve Continuous Memory DTCs.
  • Is a Continuous Memory DTC present with the KOER DTC P1101? 
 Yes For Continuous Memory DTC P0102:
Go to step 3.
For Continuous Memory DTC P0103:
Go to step 14.
All other Continuous Memory DTCs:
See DIAGNOSTIC TROUBLE CODE NUMBERS .
No Go to step 4.
3 DTC P0102: CHECK MAF SENSOR SIGNAL LOW INPUT TO PCM
  • Key OFF.
  • Check for broken/loose air outlet tube clamps (throttle body and air cleaner element ends), cracks/holes in air outlet tube, worn gaskets between MAF sensor and air cleaner element. Repair as necessary.
  • Start engine and bring to idle.
  • If a KOER DTC P0505 is present,

    See DIAGNOSTIC TROUBLE CODE NUMBERS . For A/T vehicles, if the engine stalls and cannot maintain an idle, go to step 6.

  • Run engine up to 1500 rpm for 5 seconds, then bring it back to idle.
  • Access MAF V PID.
  • Is MAF V PID less than 0.23 V? 
 Yes Go to step 5.
No Go to next step.
4 DTC P1101: CHECK FOR MAF SENSOR SIGNAL OUT OF SELF-TEST RANGE
  • Key OFF.
    NOTE: DTC P1101 can be generated by a low charged vehicle battery or the garage exhaust ventilation system. Repair the battery as necessary and remove the ventilation system and properly vent to outside atmosphere. Rerun KOEO Self Test.
  • Verify MAF sensor is connected. If not, repair as necessary.
  • Key ON, Engine Running (KOER).
  • Access MAF V PID.
  • Is MAF V PID between 0.46-2.44 V? 
 Yes Unable to identify fault at this time.
See TEST 4: INTERMITTENT
No Go to next step.
5 CHECK VPWR VOLTAGE TO MAF SENSOR
  • Key OFF.
  • Disconnect MAF sensor.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage between VPWR at the MAF sensor harness connector and negative battery post.
  • Is the voltage greater than 10.5 V? 
 Yes Go to next step.
No Repair open circuit.
Go to step 17.
6 CHECK MAF CIRCUIT SHORT TO PWR GND OR MAF RTN IN THE HARNESS
  • Disconnected PCM.
  • Disconnect NGS Tester from DLC.
  • Measure resistance between MAF and PWR GND at the MAF sensor harness connector.
  • Measure resistance between MAF and MAF RTN at the MAF sensor harness connector.
  • Is each resistance greater than 10K ohms? 
 Yes Go to next step.
No Repair short circuit.
Go to step 17.
7 CHECK MAF RTN CIRCUIT SHORT TO PWR GND IN THE HARNESS
  • Measure resistance between MAF RTN and PWR GND at the MAF sensor harness connector.
  • Is resistance greater than 10K ohms? 
 Yes Go to next step.
No Repair short circuit.
Go to step 17.
8 CHECK MAF CIRCUIT VOLTAGE CYCLING INTEGRITY
  • Reconnect PCM and NGS Tester.
  • Key ON, Engine OFF (KOEO).
  • Access MAF V PID and record the reading.
  • Jumper MAF RTN and PWR GND at the MAF sensor harness connector.

    Jumper MAF and VPWR at the MAF sensor harness connector.

  • Does the MAF V PID change from less than 0.23 V (closer to 0 V) to greater than 4.50 V? 
 Yes Replace MAF sensor.
Go to step 17
No For DTC P0102:
Go to step 9.
For DTC P1101 without P0102 present:
Go to step 10.
9 CHECK MAF CIRCUIT FOR OPEN IN HARNESS
  • Key OFF.
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Measure resistance of MAF circuit between PCM test pin 88 and MAF sensor harness connector.
  • Is the resistance less than 5.0 ohms? 
 Yes Go to next step.
No Repair open circuit.
Go to step 17.
10 CHECK PWR GND CIRCUIT FOR OPEN IN HARNESS
  • Key OFF.
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Disconnect NGS tester from DLC.
  • Measure resistance of PWR GND circuit between MAF sensor harness connector and battery negative post.
  • Is resistance less than 10.0 ohms? 
 Yes Go to next step.
No Repair open circuit.
Go to step 17.
11 CHECK MAF RTN FOR OPEN IN HARNESS
  • Measure resistance of MAF RTN circuit between PCM test pin 36 and MAF sensor harness connector.
  • Is resistance less than 5.0 ohms? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 17.
No Repair open circuit.
Go to step 17.
12 DTC P1100: CHECK MAF CIRCUIT FOR INTERMITTENT VOLTAGE TO PCM
  • Start engine.
  • If stable idle is not at least 700 rpm,
  • Symptom Troubleshooting 6, Low Idle/Stalls.

    See LOW IDLE / STALLS DURING DECELERATION .

  • Run throttle up to 1500 rpm for 5 seconds, and bring back to idle.
  • Access MAF V PID while completing the following:
    • Lightly tap on MAF sensor and wiggle harness connector to simulate road shock.
  • Is MAF V PID changing below the minimum 0.23 V or above the maximum 4.60 V? 
 Yes Inspect MAF sensor connector. If OK, replace MAF sensor.
Go to step 17.
No Go to next step.
13 CHECK FOR MAF SENSOR CIRCUIT FOR INTERMITTENT OPENS OR SHORTS
  • Access the MAF V PID.
  • Key ON, Engine OFF (KOEO).
  • Complete the following:
    • Grasp the MAF sensor harness and MAF sensor harness connector.
    • Shake and bend a small section of the harness all the way to the dash panel.
    • Wiggle, shake and bend the harness from the dash panel to the PCM.
  • Is the MAF V PID reading changing below the minimum 0.23 V or above the maximum 4.60 V? 
 Yes Repair as necessary.
Go to step 17.
No Unable to duplicate or identify fault at this time.
See TEST 4: INTERMITTENT .
14 DTC P0103: CHECK MAF SENSOR SIGNAL HIGH INPUT TO PCM
NOTE: DTC P0103: can be generated by foreign material blocking the MAF sensor screen causing an air flow restriction. If contaminants are found on the screen, check air cleaner element installation in air cleaner housing and proper sealing of air cleaner and air tubes before proceeding. Recheck for DTCs after service.
  • Start engine and bring to an idle.
  • If a KOER DTC P0505 is present,

    See DIAGNOSTIC TROUBLE CODE NUMBERS . For 2.5L A/T that stalls and cannot maintain an idle, replace PCM. See COMPUTERIZED ENGINE CONTROLS .

  • Run throttle up to 1500 rpm for 5 seconds, and bring it back to idle.
    NOTE: MAF V PID should be greater than 4.60 volts.
  • Access MAF V PID and record voltage.
  • Key OFF.
  • Disconnect MAF sensor.
  • Jumper PWR GND and MAF RTN circuits at the MAF sensor harness connector.
  • Key ON, Engine Running (KOER).
  • Did MAF V PID drop from the previous reading to below 0.23 V? 
 Yes Key OFF. Remove jumper.
Replace MAF sensor.
Go to step 17.
No Key OFF. Remove jumper.
Go to next step.
15 CHECK MAF CIRCUIT FOR SHORT TO VPWR IN HARNESS
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage between PCM test pin 88 (MAF) and PCM test pins 51, 77 and 103 (PWR GND).
  • Is the voltage less than 1.0 V? 
 Yes Go to next step.
No Repair short circuit.
Go to step 17.
16 CHECK MAF CIRCUIT FOR SHORT TO VREF IN HARNESS
  • Key OFF.
  • Measure resistance between PCM test pin 88 (MAF) and PCM test pin 90 (VREF).
  • Is resistance greater than 10K ohms? 
 Yes If an idle concern is not present:
Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
If a fault was not detected and an idle concern is still present:
Disregard DTC P0103 at this time.
Go to step 17.
No Repair short circuit.
Go to step 17.
17 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear DTCs from PCM memory using NGS tester generic OBD-II function.
  • Perform PCM Quick Test.
  • Is same DTC present? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Repeat PCM Quick Test.
No If any other DTC is present, go to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
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