Inspection Procedure

HINT:

Read freeze frame data. Freeze frame data records engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0441, P0442, P0446 AND/OR P0456)iquest 

   Result 

   DTC OUTPUT RESULT
   
   

   Display (DTC output)	Proceed to
   Only P0441, P0442, P0446 and/or P0456 are output	A
   P0451, P0452 and P453 are output	B

   HINT:

   If any other DTCs besides P0441, P0442, P0446 and/or P0456 are output, perform the troubleshooting for those DTCs first (reference: P0451, P0452, P0453 are vapor pressure sensor malfunctions).

   B: Go to RELEVANT  DIAGNOSTIC TROUBLE CODE CHART  

   A: GO TO NEXT STEP 

2. CHECK CURRENT AND PENDING DTC 
   1. Check current DTCs. Select the hand-held tester menus: DIAGNOSIS, ENHANCED OBDII, DTC INFO and CURRENT DTCS.
   2. Check pending DTCs. Select the hand-held tester menus: DIAGNOSIS, ENHANCED OBDII, DTC INFO and PENDING DTCS.

   Result 

   CURRENT AND PENDING DTC RESULT
   
   

   Current DTC	Pending DTC	Conclusion
   Set	Set	System has been malfunctioning. Problem can be specified.
   Set	-	System was malfunctioning in previous driving cycle. Problem may be specified.
   -	Set	System is malfunctioning. This is intermittent problem and caused by fuel tank cap loosing. Otherwise, this problem may be difficult to eliminate.

   HINT:

   The ECM stores the current DTC and illuminates the MIL when an emission-related component is malfunctioning in 2 consecutive driving cycles (2 trips). The MIL is turned OFF, if the component is functioning normally in 3 consecutive driving cycles. The ECM erases the current DTC, if the component is functioning normally in 40 consecutive driving cycles.

   The ECM stores the pending DTC when If the component is malfunctioning in present driving cycle (1 trip). The ECM erases the pending DTC, if the component is functioning normally in the next driving cycle.

   NEXT: GO TO NEXT STEP 

3. PREDICT POSSIBLE MALFUNCTION AREA 

   Find the DTC in the table below to suspect a malfunction area.

   EVAP DTC Matrix 

   Fig 1: EVAP DTC Matrix Chart

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   MALFUNCTION AREA DTC
   
   

   DTCs	Suspected Malfunction Area
   P0441 only	EVAP VSV stuck open
   P0446 only	CCV (vent valve) stuck open
   P0442 and/or P0456	Small leak

   NEXT: GO TO NEXT STEP 

4. PERFORM EVAP SYSTEM CHECK 
   NOTE: The EVAP system check can be used for confirmation after the EVAP system repair. Check DTCs after performing the EVAP system check. If no pending DTC is set, the EVAP system is functioning normally and the repair is completed.
   1. Select the "mmHg" unit. Select the hand-held tester menus: DIAGNOSIS, SETUP, UNIT CONVERSION and VAPOR PRESS.
   2. Allow the engine to idle.
   3. Perform the EVAP system check to find a malfunction area. Select the hand-held tester menus: DIAGNOSIS, ENHANCED OBD II, SYSTEM CHECK and LEV II SYS CHECK.
   4. Read NOTICE and press ENTER.

   HINT:

   The EVAP system check is most accurate when the following conditions are being set:

   • Atmospheric pressure is 762 mmHg (sea level).
   • The engine coolant and intake air temperatures are 4 to 35°C (40 to 90°F).
   • The fuel tank level is 1/4 to 3/4.

   Diagram of LEVII EVAP System Check 

   Fig 2: LEVII EVAP System Check Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NEXT: GO TO NEXT STEP 

5. EVAP SYSTEM CHECK STEP   1  (INITIALIZE SYSTEM) 
   Fig 3: Initialize System Check Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Wait for 30 seconds.

   Fig 4: EVAP System Check (Initialize System) Display

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. EVAP SYSTEM CHECK STEP   2  (CHECK FOR CCV) 
   Fig 5: CCV Check Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Press RIGHT to go to step  2.
   2. Wait for 30 seconds and check VAPOR PRESS (EVAP pressure).
      Fig 6: EVAP System Check (CCV) Display

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Result 

   Fig 7: Vapor Pressure Check Result Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   In this step, the intake manifold pressure (vacuum) is applied to the EVAP system. However, the fuel tank pressure does not drop due to the CCV (vent valve) open.

   NG: Go to step   11 

   OK: GO TO NEXT STEP 

7. EVAP SYSTEM CHECK STEP   3  (INITIALIZE SYSTEM) 
   Fig 8: Initialize System Check Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Press RIGHT to go to step  3.
   2. Wait for 30 seconds.
      Fig 9: EVAP System Check (Initialize System) Display

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NEXT: GO TO NEXT STEP 

8. EVAP SYSTEM CHECK STEP   4  (CHECK FOR EVAP VSV STUCK OPEN) 
   Fig 10: EVAP VSV Check Diagram

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Press RIGHT to go to step  4.
   2. Wait for 15 seconds and check VAPOR PRESS (EVAP pressure).
      Fig 11: EVAP System Check (EVAP VSV Stuck Open) Display

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Result 

   VAPOR PRESSURE CHECK RESULT
   
   

   VAPOR PRESS	Conclusion	Proceed to
   Higher than 758 mmHg-a (-4 mmHg-g)	Trouble area has not been found yet.	OK
   Lower than 758 mmHg-a (-4 mmHg-g)	EVAP VSV stuck open	NG

   NG: Go to step   15 

   OK: GO TO NEXT STEP 

9. EVAP SYSTEM CHECK STEP   5  (APPLYING VACUUM) 
   Fig 12: EVAP System (Applying Vacuum) Check

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Press RIGHT to go to step  5.
   2. Wait for 30 seconds and check VAPOR PRESS (EVAP pressure).
      Fig 13: EVAP System Check (Applying Vacuum) Display

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Result 

   Fig 14: Vapor Pressure Check Result Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002