Description Of EVAP System Check

WARNING: This page is about a different car, the 2004 Toyota Camry Solara. However, it is still accessible from the selected car via links, so may be relevant.

Below is an outline of this section.

EVAP SYSTEM SPECIFICATION

1. SYSTEM CHECK OVERVIEW	Purpose of EVAP system check
DETAILS OF "LEV II SYS CHECK"	Diagram of each VSV motion and the changes of tank's interior pressure while performing EVAP system check
2. SYSTEM CHECK PREPARATION	Description of things to keep in mind before starting system check
3. CONDUCT LEV II SYSTEM CHECK	Helpful notes when performing the system check
4. HAND-HELD TESTER OPERATION PROCEDURE TO PERFORM EVAP SYSTEM CHECK	Illustrations and operational procedures

SYSTEM CHECK OVERVIEW

The EVAP system check is an organized method of identifying situations that may cause a monitor to fail. Use the check to troubleshoot the following DTCs.

SYSTEM CHECK OVERVIEW SPECIFICATION

P0441	EVAP VSV (Purge) malfunction
P0446	CCV (Vent) malfunction
P0442	Small leak
P0456	Very small leak

The system check can also be used to confirm that repairs have been made properly. After repairing the EVAP system, perform the LEV II SYS CHECK again to confirm that the system is operating normally.

Fig 1: Identifying LEV II SYS Check Diagram

The EVAP system LEV II SYS CHECK is designed to confirm proper operation of the EVAP VSV and CCV, and determine if a leak or restriction is present in the system. During the check, the EVAP VSV and CCV are controlled in specific patterns to create negative pressure and/or restore ambient pressure to EVAP system. The hand-held tester displays the FTP sensor's value as these changes occur. By comparing the changes in the FTP sensor value to the expected results, suspect areas can be identified.

SYSTEM CHECK PREPARATION
Do not disturb the vehicle. Wiggling lines or tightening the gas cap before this test is conducted may affect the results of this test. The vehicle should be left in the condition it was in when the DTC was set.
NOTE:
The EVAP system pressure can be affected by ambient temperature, pressure, and fuel level. This test is most accurate when the following conditions are met.
- The vehicle is at sea level and at an ambient pressure of approximately 762 mmHg-a (0 mmHg-g)
- The external fuel tank temperature is between 4 to 35°C (40 to 90°F).
- The fuel level in the fuel tank is approximately 1/4 to 3/4 full.
CONDUCT LEV IL SYS CHECK
Below are descriptions of these situations:
- When, during the LEV II SYS CHECK, the EVAP VSV is automatically closed or the LEV II SYS CHECK is automatically aborted.
- When a conversion of units is necessary.
NOTE: If the pressure drops below 740 mmHg-a (-22 mmHg-g) at any point during this test, the hand-held tester will close the VSV for EVAP to prevent system damage.
If the pressure drops below 735 mmHg-a (-27 mmHg-g), the hand-held tester will abort the LEV II SYS CHECK.

Fig 2: Displaying LEV II SYS CHECK
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 3: Displaying ERROR
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HINT:

If the vapor pressure value needs to be converted to a different unit standard, select the following menus on the hand-held tester: DIAGNOSIS/SETUP/UNIT CONVERSION/VAPOR PRESS.

(ABS: 762 mmHg-a ambient pressure)

(gauge: 0 mmHg-g ambient pressure)

Fig 4: Displaying Unit Conversion
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
HAND-HELD TESTER OPERATION PROCEDURE TO PERFORM SYSTEM CHECK
1. Connect the hand-held tester to the DLC3.
2. Start the engine.
3. Enter the following menus:
  DIAGNOSIS/ENHANCED OBD II/SYSTEM CHECK.
  
  Fig 5: Displaying SYSTEM CHECK Mode
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Select LEV II SYS CHECK.
  
  Fig 6: Displaying LEV II SYS CHECK Mode
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Read the NOTICE and press ENTER.
  
  Fig 7: Displaying NOTICE
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Read the NOTICE and press ENTER.
  
  Fig 8: Displaying press ENTER Mode (1 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
7. Read the NOTICE and press ENTER.
  
  Fig 9: Displaying press ENTER Mode (2 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
8. Press ENTER
9. Starting with the next step, perform inspections according to the hand-held tester system check displays.
10. Perform EVAP system check procedure (see SYSTEM CHECK PROCEDURE BY OPERATION OF HAND-HELD TESTER ).
Fig 10: Displaying EVAP System Check Mode
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002