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Home >> Mazda >> 2011 >> RX-8 R3, 1.3 4 >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P0102
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DTC P0102

DTC P0102 MAF sensor circuit low input
DETECTION CONDITION 
  • The PCM monitors the input voltage from the MAF sensor when the engine is running. If the input voltage is less than 0.64 V,  the PCM determines that the MAF sensor circuit input voltage is low.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • MAF/IAT sensor connector or terminals malfunction
  • Short to ground or open circuit in MAF sensor power supply circuit
    • Short to ground in wiring harness between main relay terminal C and MAF/IAT sensor terminal A
    • MAF/IAT sensor related fuse malfunction
    • Open circuit in wiring harness between main relay terminal C and MAF/IAT sensor terminal A
  • Short to ground in wiring harness between MAF/IAT sensor terminal C and PCM terminal 1AK
  • PCM connector or terminals malfunction
  • Open circuit in wiring harness between MAF/IAT sensor terminal C and PCM terminal 1AK
  • MAF sensor malfunction
  • PCM malfunction
G07878100
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT MAF/IAT SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the MAF/IAT sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 9.
No Go to the next step.
4 INSPECT MAF SENSOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • MAF/IAT sensor connector is disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between MAF/IAT sensor terminal A (wiring harness-side) and body ground.
  • Is the voltage B+? 
 Yes Go to the next step.
No Inspect the MAF/IAT sensor related fuse.
  • If the fuse is melt:
    • Repair or replace the wiring harness for a possible short to ground.
    • Replace the fuse.
  • If the fuse is deterioration:
    • Replace the fuse.
  • If the fuse is normal:
    • Repair or replace the wiring harness for a possible open circuit.

Go to Step 9.
5 INSPECT MAF SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • MAF/IAT sensor connector is disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between MAF/IAT sensor terminal C (wiring harness-side) and body ground.
  • Is there continuity?
 Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:
Go to Step 9.
No Go to the next step.
6 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 9.
No Go to the next step.
7 INSPECT MAF SENSOR SIGNAL CIRCUIT FOR OPEN CIRCUIT 
  • MAF/IAT sensor and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between MAF/IAT sensor terminal C (wiring harness-side) and PCM terminal 1AK (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
8 INSPECT MAF SENSOR 
 Yes Replace the MAF/IAT sensor, then go to the next step.
(See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
9 VERIFY TROUBLESHOOTING OF DTC P0102 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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