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Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3 With TC] >> DTC P0443 >> Diagnostic procedure
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Diagnostic procedure

DTC P0443 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA been recorded?
Yes Go to the next step.
No Record FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Check for related Service Bulletins and/or online repair information availability.
  • Is any related repair information available?
Yes Perform the 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 the purge solenoid valve tube that is connected to the intake manifold.
  • Connect the vacuum pump to the purge solenoid valve.
  • Pump the vacuum pump several times and stop.
  • Wait a few seconds. 
  • Is the 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 the purge solenoid valve connector.
  • Pump the vacuum pump several times and wait a few seconds  .
  • Is the vacuum maintained?
Yes Repair or. replace the wiring harness for a 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 (damaged/pulled-out pins, corrosion, etc)..
  • Is there any 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 ignition switch to the ON position (Engine off).
  • Measure the voltage between purge solenoid valve connector terminal A and body ground.
  • Is the voltage B+  ?
Yes Go to the next step.
No Repair or replace the wiring harness for an 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 (damaged/pulled-out pins, corrosion, etc)..
  • Is there any 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 ignition switch to the ON position (Engine off).
  • Measure voltage between purge solenoid valve terminal B (harness-side) and body ground.
  • Is the voltage B+  ?
Yes Repair or replace the wiring harness for a short to power supply, then go to the next step.
No Inspect for continuity between purge solenoid valve terminal B (harness-side) and PCM terminal 4T (harness-side).
  • If there is continuity, go to the next step.
  • If there is no continuity, repair or replace the wiring harness for an open circuit, then go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P0443 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Turn the ignition switch off.
  • Start the engine and warm it up completely.
  • Is the PENDING CODE for this DTC present?
Yes Replace 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 inspection.
(See DTC TABLE ).
No Troubleshooting completed.