P0441

DTC P0441: Evaporative Emission Control System Incorrect Purge Flow










TECHNICAL DESCRIPTION

- ECM detects a stuck open condition of evaporative emission purge solenoid and a stuck closed condition of evaporative emission ventilation solenoid by pressure change in fuel tank.
- Stuck open evaporative emission purge solenoid is judged through monitoring leak of evaporative emission system.
- Stuck closed evaporative emission ventilation solenoid is judged after 20 seconds from end of monitoring leak of evaporative emission system, or of usual operation of evaporative emission purge solenoid from ON to OFF.

DESCRIPTIONS OF MONITOR METHODS

Fuel tank pressure decreases largely during purge-cut.

MONITOR EXECUTION

Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- Fuel tank differential pressure sensor monitor
Sensor (The sensor below is determined to be normal)

- Not applicable

DTC SET CONDITIONS

Logic Flow Chart





Check Conditions

- Engine is running.
- ON duty cycle of the evaporative emission purge solenoid is 0 percent.
- 20 seconds have elapsed since the duty cycle of the evaporative emission purge solenoid has turned to 0 percent.
Judgement Criterion

- The pressure in the fuel tank is -1.96 kPa (-0.58 in.Hg) or less for 0.1 second.

FAIL-SAFE AND BACKUP FUNCTION

- None

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 4 Monitors, Trips, Drive Cycles and Readiness Codes .

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)

- Evaporative emission purge solenoid failed.
- Evaporative emission ventilation solenoid failed.
- Fuel tank differential pressure sensor circuit related part(s) failed.

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).





CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK"
(OFF) position before connecting or disconnecting scan tool MB991958.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Read the DTC.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is DTC P0451 set?

YES Refer to DTC P0451 - Fuel Tank Differential Pressure Circuit Range/Performance Problem P0451.

NO Go to Step 2.

STEP 2. Using scan tool MB991958, check data list item 52: Fuel Tank Differential Pressure Sensor.

(1)Turn the ignition switch to the "ON" position.

(2)Remove the fuel cap.

(3)Set scan tool MB991958 to the data reading mode for item 52, Fuel Tank Differential Pressure Sensor.

- The fuel tank differential pressures should be 1,500 and 3,500 millivolts.

(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the fuel tank pressure between 1,500 and 3,500 millivolts?

YES Go to Step 3.
NO Refer to DTC P0451 - Fuel Tank Differential Pressure Circuit Range/Performance Problem P0451.
STEP 3. Using scan tool MB991958, check actuator test item 10: Evaporative Emission Purge Solenoid.

(1)Turn the ignition switch to the "ON" position.

(2)Set scan tool MB991958 to the actuator test mode for item 10, Evaporative emission purge solenoid.

- An operation sound should be heard and vibration should be felt when the evaporative emission purge solenoid is operated.

(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the solenoid operating properly?

YES Go to Step 4.
NO Replace the evaporative emission purge solenoid. Then go to Step 5.
STEP 4. Using scan tool MB991958, check actuator test item 15: Evaporative Emission Ventilation Solenoid.

(1)Turn the ignition switch to the "ON" position.

(2)Set scan tool MB991958 to the actuator test mode for item 15, Evaporative emission ventilation solenoid.

- An operation sound should be heard and vibration should be felt when the evaporative emission ventilation solenoid is operated.

(3)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the solenoid operating properly?

YES Repair or replace the vent hose and air filter. Then go to Step 5.
NO Replace the evaporative emission ventilation solenoid. Then go to Step 5.
STEP 5. Test the OBD-II drive cycle.

(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 4 Monitors, Trips, Drive Cycles and Readiness Codes.

(2)Read the diagnostic trouble code.

Q. Is DTC P0441 set?

YES Retry the troubleshooting.
NO The inspection is complete.