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Diagnostic procedure

DTC P0103 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has FREEZE FRAME DATA been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Technical Service Bulletin(s) 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 POOR CONNECTION OF MAF SENSOR CONNECTOR 
  • 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 terminals, then go to Step 7.
No Go to the next step.
4 INSPECT MAF SIGNAL CIRCUIT FOR SHORT TO POWER CIRCUIT 
  • Turn the ignition switch to the ON position. (Engine off)
  • Measure the voltage between MAF/IAT sensor terminal C (wiring harness-side) and body ground.
  • Is the voltage 0 V  ?
Yes Go to the next step.
No Repair or replace the wiring harness, then go to Step 7.
5 INSPECT POOR CONNECTION OF PCM CONNECTOR 
  • 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 the terminal, then go to Step 7.
No Go to the next step.
6 INSPECT MAF SENSOR GROUND FOR OPEN CIRCUIT 
  • Remove the PCM with the PCM connector connected.
  • Inspect for continuity between MAF/IAT sensor terminal B (wiring harness-side) and GND.
  • Is there continuity?
Yes Replace MAF/IAT sensor, then go to the next step. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF] , INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3] .)
No Repair or replace the wiring harness, then go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0103 COMPLETED 
  • Make sure to reconnect all the disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine.
  • 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.
8 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC troubleshooting. (See DTC TABLE )
No Troubleshooting completed.