Mazda DTC P0443 Diagnostic

DTC P0443	Purge solenoid valve circuit problem
DETECTION CONDITION	• The PCM monitors the input voltages from the purge solenoid valve. If the voltage at PCM terminal 2AN remains low or high, the PCM determines that the purge solenoid valve circuit has malfunction. 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. • FREEZE FRAME DATA is available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• Purge solenoid valve malfunction • Connector or terminal malfunction • Short to ground in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN • Open circuit in wiring harness between main relay and purge solenoid valve terminal B • Open circuit in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN • Short to power supply in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN • PCM malfunction

DTC P0443

Purge solenoid valve circuit problem

DETECTION CONDITION

• The PCM monitors the input voltages from the purge solenoid valve. If the voltage at PCM terminal 2AN remains low or high, the PCM determines that the purge solenoid valve circuit has malfunction.

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.

• FREEZE FRAME DATA is available.

• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Purge solenoid valve malfunction

• Connector or terminal malfunction

• Short to ground in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN

• Open circuit in wiring harness between main relay and purge solenoid valve terminal B

• Open circuit in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN

• Short to power supply in wiring harness between purge solenoid valve terminal A and PCM terminal 2AN

• PCM malfunction

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.
1		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 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.
2		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.
3		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.
4		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.
5		No	Go to the next step.
6	INSPECT PURGE SOLENOID VALVE • Perform purge solenoid valve inspection. • Is purge solenoid valve normal?	Yes	Go to the next step.
6		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.
7		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.
8		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.
9		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.
10		No	Go to the next step.
11	VERIFY AFTER REPAIR PROCEDURE • Perform the “After Repair Procedure”. • Are any DTC present?	Yes	Go to the applicable DTC troubleshooting.
11		No	Troubleshooting completed.