Code No. P0459: Purge Control Solenoid Valve Circuit High Input

OPERATION

Power is supplied to the purge control solenoid valve connector terminal from the engine control relay connector terminal.
The engine-ECU connector terminal PURG makes the power transistor in the unit be in ON position, and that makes currents go on the purge control solenoid valve connector terminal.

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 JUDGEMENT

Check Conditions

Engine is being cranked.
Battery positive voltage is more than 10 V and is less than 16.5 V.

Judgement Criteria

The solenoid current is more than 2.3 A with the purge control solenoid driving.

FAIL-SAFE AND BACKUP FUNCTION

None

PROBABLE CAUSES

Failed purge control solenoid valve
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. Perform resistance measurement at purge control solenoid valve connector.

Disconnect connector, and measure at solenoid valve side.
Resistance between terminals.

OK: 22 - 26 Ω (at 20°C)

Q. Is the check result normal?

	Go to Step 3.

	Repair or replace the connector, or replace the purge control solenoid valve.

STEP 3. Perform voltage measurement at engine-ECU connector.

Disconnect connector, and measure at harness side.
Ignition switch: "ON"
Voltage between terminal PURG and body earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 4.

	Repair or replace the connector, or check and repair harness between purge control solenoid valve connector terminal and engine-ECU connector terminal PURG. Check output line for short circuit.

STEP 4. Check harness between purge control solenoid valve connector terminal and engine-ECU connector terminal PURG.

Check output line for damage.

Q. Is the check result normal?

	Go to Step 5.

	Repair or replace the connector, or repair the damaged harness wire.

STEP 5. 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.