DTC P0441 Evaporative Emission Control System Incorrect Purge Flow
DTC SUMMARY
DESCRIPTION
The circuit description can be found in the EVAP (Evaporative Emission) System.
INSPECTION PROCEDURE
Refer to the EVAP System.
MONITOR DESCRIPTION
The two monitors, Key-Off and Purge Flow, are used to detect malfunctions relating to DTC P0441. The Key-off monitor is initiated by the ECM internal timer, known as the soak timer, 5 hours*1 after the ignition switch is turned off. The purge flow monitor runs while the engine is running.
1. KEY-OFF MONITOR
5 hours*1 after the ignition switch is turned off, the electric vacuum pump creates negative pressure (vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.
HINT: *1: If the engine coolant temperature is not below 35C (95F) 5 hours after the ignition switch is turned off, the monitor check starts 2 hours later. If it is still not below 35C (95F) 7 hours after the ignition switch is turned off, the monitor check starts 2.5 hours later.
*2: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
The ECM illuminates the MIL and sets the DTC (2 trip detection logic).
2. PURGE FLOW MONITOR
The purge flow monitor consists of the two step monitors.
The 1st monitor is conducted every time and the 2nd monitor is activated if necessary.
Atmospheric pressure check: In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before and after conduction of the purge flow monitor, is measured by the ECM.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All:
Purge flow:
Purge VSV stuck open and closed:
Key-off monitor sequence 1 to 8
1. Atmospheric pressure measurement
2. First reference pressure measurement
3. EVAP canister vent valve close stuck check
4. Vacuum introduction
5. EVAP canister purge valve close stuck check
6. Second reference pressure measurement
7. Leak check
8. Atmospheric pressure measurement
TYPICAL MALFUNCTION THRESHOLDS
Purge flow:
EVAP VSV stuck open:
EVAP VSV stuck closed:
MONITOR RESULT
Refer to CHECKING MONITOR STATUS
Basic inspection
(a) WHEN MEASURING RESISTANCE OF
ELECTRONIC PARTS
(1) Unless otherwise stated, all resistance
measurements should be made at an ambient
temperature of 20°C (68°F). Resistance
measurements may be inaccurate if measured
at high temperatures, i.e. immediately after the
vehicle has been running ...
Access monitor result
(A) select the following menus on the intelligent tester:
diagnosis, enhanced obdii, monitor info
and monitor result. The monitor status
appears after the component name.
INCMP: The component has not been monitored
yet.
PASS: The component is functioning normally.
FAIL: The component is ...
Air outlet control servo motor
ON-VEHICLE INSPECTION
1. INSPECT AIR OUTLET CONTROL SERVO MOTOR
(a) Remove the air outlet control servo motor.
(b) Connect the positive (+) lead from the battery to
terminal 4 and negative (-) lead to terminal 5, then
check that the lever turns to "DEF" position.
(c) Connect ...