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Home >> Mazda >> 2021 >> CX-3 AWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control (1 Of 5) >> DTC P0103-00: MAF Sensor Circuit High Input >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0103:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
 - 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 DETERMINE IF MAF SENSOR OR WIRING HARNESS MALFUNCTION
  • Access the MAF PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .)
  • Verify the MAF PID value.
  • Is the MAF PID value 5 V or B+?
 Yes Go to Step 7.
No Go to the next step.
4 INSPECT MAF SENSOR/IAT SENSOR NO. 1 CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the MAF sensor/IAT sensor No. 1 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.
5 INSPECT PCM CONNECTOR CONDITION
  • 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.
6 INSPECT MAF SENSOR Yes Replace the MAF sensor/IAT sensor No. 1, then go to Step 9.
(See MASS AIR FLOW (MAF) SENSOR/INTAKE AIR TEMPERATURE (IAT) SENSOR NO. 1 REMOVAL/INSTALLATION .)
No Go to Step 9.
7 INSPECT MAF SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Switch the ignition off.
  • Disconnect the MAF sensor/IAT sensor No. 1 connector.
  • Access the MAF PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .)
  • Verify the MAF PID value.
  • Is the MAF PID value 5 V or B+?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between MAF sensor/IAT sensor No. 1 terminal C and PCM terminal 2BC.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to power supply.

Go to Step 9.
No Go to the next step.
8 INSPECT MAF SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
  • Verify that the MAF sensor/IAT sensor No. 1 connector is disconnected.
  • Switch the ignition off.
  • Disconnect the PCM connector.
  • Inspect for continuity between MAF sensor/IAT sensor No. 1 terminal B (wiring harness-side) and PCM terminal 2AY (wiring harness-side).
  • Is there continuity?
 Yes Replace the MAF sensor/IAT sensor No. 1, then go to the next step.
(See MASS AIR FLOW (MAF) SENSOR/INTAKE AIR TEMPERATURE (IAT) SENSOR NO. 1 REMOVAL/INSTALLATION .)
No Refer to the wiring diagram and verify whether or not there is a common connector between MAF sensor/IAT sensor No. 1 terminal B and PCM terminal 2AY.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to the next step.
9 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Always 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 Repeat the inspection from Step 1.
Go to the next step.
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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