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Diagnostic procedure

DTC P0403 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 EGR VALVE 
  • Turn the ignition switch off.
  • Disconnect EGR valve connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the terminals and/or connector, then go to Step 10.
No Go to the next step.
4 INSPECT POWER CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage following terminal and body ground.
    • EGR valve terminal C
    • EGR valve terminal D
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace harness for open circuit then go to Step 10.
5 INSPECT EGR VALVE  Yes Go to the next step.
No Replace the EGR valve, then go to Step 10.
6 INSPECT FOR CONTROL CIRCUIT FOR SHORT TO GROUND 
  • Turn the ignition switch off.
  • Inspect for continuity following terminal and body ground:
    • EGR valve terminal E
    • EGR valve terminal A
    • EGR valve terminal B
    • EGR valve terminal F
  • is there continuity?
 Yes Repair or replace wiring harness for short to ground, then go to Step 10.
No Go to the next step.
7 INSPECT FOR CONTROL CIRCUIT FOR SHORT TO POWER 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage following terminal and body ground:
    • EGR valve terminal E
    • EGR valve terminal A
    • EGR valve terminal B
    • EGR valve terminal F
  • Is the voltage B+  ?
 Yes Repair or replace wiring harness for short to power supply, then go to Step 10.
No Go to the next step.
8 INSPECT POOR CONNECTION OF PCM 
  • 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 terminals and/or connector, then go to Step 10.
No Go to the next step.
9 INSPECT CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • Remove the PCM with the PCM connector connected.
  • Inspect for continuity following terminals:
    • Between EGR valve terminal E and PCM terminal 2AU
    • Between EGR valve terminal A and PCM terminal 2AR
    • Between EGR valve terminal B and PCM terminal 2AY
    • Between EGR valve terminal F and PCM terminal 2AV
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for open circuit then go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P0403 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear The DTC from the PCM memory using the WDS or equivalent.
  • Start the engine.
  • Is the PENDING CODE for this DTC present?
 Yes Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
11 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC troubleshooting. (See DTC TABLE )
No Troubleshooting completed.
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