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Diagnostic procedure

DTC P0443 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 CLASSIFY OPEN CIRCUIT OR SHORT TO GROUND MALFUNCTION 
  • Disconnect purge solenoid valve tube that is connected to intake manifold.
  • Connect vacuum pump to purge solenoid valve.
  • Pump vacuum pump several times and stop.
  • Wait a few seconds. 
  • Is vacuum maintained?
 Yes Go to Step 5.
No Go to the next step.
4 INSPECT PASSAGE CONTROL OF PURGE SOLENOID VALVE 
  • Turn the ignition switch off.
  • Disconnect purge solenoid valve connector.
  • Pump vacuum pump several times and wait a few seconds. 
  • Is vacuum maintained?
 Yes Repair or replace wiring harness for short to ground, then go to Step 10.
No Replace the purge solenoid valve, then go to Step 10.
5 INSPECT PURGE SOLENOID VALVE CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there malfunction?
 Yes Repair or replace the terminal, then go to Step 10.
No Go to the next step.
6 INSPECT PURGE SOLENOID VALVE  Yes Go to the next step.
No Replace the purge solenoid valve, then go to Step 10.
7 INSPECT PURGE SOLENOID VALVE POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between purge solenoid valve terminal B and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness for open circuit, then go to Step 10.
8 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 malfunction?
 Yes Repair or replace the terminal, then go to Step 10.
No Go to the next step.
9 INSPECT PURGE SOLENOID VALVE CONTROL CIRCUIT 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between purge solenoid valve terminal A (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the wiring harness for short to power supply, then go to the next step.
No Inspect for continuity between purge solenoid valve terminal A (wiring harness-side) and PCM terminal 2AN (wiring harness-side).
  • If there is continuity, go to the next step.
  • If there is no continuity, repair or replace wiring harness for open circuit, then go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P0443 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • 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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