Code No. P0443: Purge Control Solenoid Valve System

OPERATION

Power is supplied to the purge control solenoid valve (terminal No. 2) from the engine control relay (terminal No. 2).
The engine-ECU (terminal No. 37) makes the power transistor in the unit be in ON position, and that makes currents go on the purge control solenoid valve (terminal No. 1).

FUNCTION

In response to a signal from the engine-ECU, the purge control solenoid valve controls the flow rate of the purge air to be introduced into the inlet manifold.

TROUBLE JUDGMENT

Check Conditions

Engine is being cranked.
Battery positive voltage is more than 11 V and is less than 16.5 V.

Judgement Criteria

The purge control solenoid valve coil surge voltage (battery positive voltage + 2 V) is not detected.
The engine-ECU monitors for this condition once during the drive cycle.

Check Conditions

Battery positive voltage is more than 11 V and is less than 16.5 V.
ON duty cycle of the purge control solenoid valve is more than 10 % and is less than 90 %.
More than 1 second has elapsed after the above mentioned conditions have been met.

Judgement Criterion

The purge control solenoid valve coil surge voltage (battery positive voltage + 2 V) is not detected for 1 second after the purge control solenoid valve is turned off.

PROBABLE CAUSES

Failed purge control solenoid valve
Open/short circuit or harness damage in purge control solenoid value circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test

Item 10: Purge control solenoid valve

OK: Operating sound can be heard and the valve vibrates

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Go to Step 2 .

STEP 2. Connector check: B-07 purge control solenoid valve connector

Q. Is the check result normal?

	Go to Step 3 .

	Repair or replace the connector.

STEP 3. Perform resistance measurement at B-07 purge control solenoid valve connector.

Disconnect connector, and measure at solenoid valve side.
Resistance between terminal No. 1 and No. 2.

OK: 22 - 26 Ω (at 20°C)

Q. Is the check result normal?

	Go to Step 4 .

	Replace the purge control solenoid valve.

STEP 4. Perform voltage measurement at B-07 purge control solenoid valve connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal No. 2 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 6 .

	Go to Step 5 .

STEP 5. Connector check: A-33X engine control relay connector

Q. Is the check result normal?

	Check intermediate connector A-11, and repair if necessary. If intermediate connector is normal, check and repair harness between B-07 (terminal No. 2) purge control solenoid valve connector and A-33X (terminal No. 2) engine control relay connector. Check power supply line for open/short circuit.

	Repair or replace the connector.

STEP 6. Connector check: B-08 engine-ECU connector

Q. Is the check result normal?

	Go to Step 7 .

	Repair or replace the connector.

STEP 7. Perform voltage measurement at B-08 engine-ECU connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal No. 37 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 8 .

	Check and repair harness between B-07 (terminal No. 1) purge control solenoid valve connector and B-08 (terminal No. 37) engine-ECU connector. Check output line for open/short circuit.

STEP 8. Check harness between B-07 (terminal No. 1) purge control solenoid valve connector and B-08 (terminal No. 37) engine-ECU connector.

Check output line for damage.

Q. Is the check result normal?

	Go to Step 9 .

	Repair the damaged harness wire.

STEP 9. Check harness between B-07 (terminal No. 2) purge control solenoid valve connector and A-33X (terminal No. 2) engine control relay connector.

note

Before checking harness, check intermediate connector A-11, and repair if necessary.

Check power supply line for damage.

Q. Is the check result normal?

	Go to Step 10 .

	Repair the damaged harness wire.

STEP 10. M.U.T.-III actuator test

Item 10: purge control solenoid valve

OK: Operating sound can be heard and the valve vibrates

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace the engine-ECU.