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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P0443 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0443 DIAGNOSTIC PROCEDURE TABLE

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 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 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.
(See PURGE SOLENOID VALVE REMOVAL/INSTALLATION .)
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.
(See PURGE SOLENOID VALVE REMOVAL/INSTALLATION .)
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 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 (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 the harness at between purge solenoid valve terminal A (wiring harness-side) and PCM terminal 2C (wiring harness-side) for open or short circuit.
  • 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.
  • 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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