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DTC P0443

DTC P0443 Purge solenoid valve circuit problem
DETECTION CONDITION 
  • Detect any of the following condition:
    • The control voltage of the purge solenoid valve is less than specification even though the purge solenoid valve is off.
    • The current in the output driver IC over-current detection circuit above 3.5 A  even though the purge solenoid valve is ON.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Purge solenoid valve connector or terminals malfunction
  • Short to ground or open circuit in purge solenoid valve power supply circuit
    • Short to ground in wiring harness between main relay terminal C and purge solenoid valve terminal A
    • Purge solenoid valve related fuse malfunction
    • Open circuit in wiring harness between main relay terminal C and purge solenoid valve terminal A
  • Short to ground in wiring harness between purge solenoid valve terminal B and PCM terminal 2C
  • Purge solenoid valve malfunction
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between purge solenoid valve terminal B and PCM terminal 2C
  • Open circuit in wiring harness between purge solenoid valve terminal B and PCM terminal 2C
  • PCM malfunction
G07878119
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) 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 INSPECT PURGE SOLENOID VALVE CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the purge solenoid valve connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 10.
No Go to the next step.
4 INSPECT PURGE SOLENOID VALVE POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • Purge solenoid valve connector is disconnected.
  • 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 Go to the next step.
No Inspect the purge solenoid valve related fuse.
  • If the fuse is melt:
    • Repair or replace the wiring harness for a possible short to ground.
    • Replace the fuse.
  • If the fuse is deterioration:
    • Replace the fuse.
  • If the fuse is normal:
    • Repair or replace the wiring harness for a possible open circuit.

Go to Step 10.
5 INSPECT PURGE SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO GROUND 
  • Purge solenoid valve connector is disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between purge solenoid valve terminal B (wiring harness-side) and body ground.
  • Is there continuity?
 Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:
Go to Step 10.
No Go to the next step.
6 INSPECT PURGE SOLENOID VALVE 
 Yes Replace the purge solenoid valve, then go to Step 10.
No Go to the next step.
7 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 any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 10.
No Go to the next step.
8 INSPECT PURGE SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Purge solenoid valve and PCM connectors are disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between purge solenoid valve terminal B (wiring harness-side) and body ground.
  • Is the voltage B+? 
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 10.
No Go to the next step.
9 INSPECT PURGE SOLENOID VALVE CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • Purge solenoid valve and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between purge solenoid valve terminal B (wiring harness-side) and PCM terminal 2C (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible 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 M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the PENDING CODE same as 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 inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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