Page 673 of 4323

A23501
ON
Within 15 minutes
2/5
0.02 inch Orifice High±flow
Vent Valve Stuck closed
OK
0.02 inch Orifice Clogged
60
sec
3/5
4 sec
Vacuum Pump Stuck OFF
ONON
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
Negative
Steps
(Reference)TimeON: Open
OFF: Closed
OFF: Vent ON: Closed
Leak Pressure First 0.02 inch
Standard
± DIAGNOSTICSENGINE
DI±471
665 Author: Date:
2005 SEQUOIA (RM1146U)
6 Perform EVAP system step 2/5 check.
HINT:
Make a note of the pressures checked in steps (a) and (b) below.
(a) Check the EVAP pressure 4 seconds after the vacuum pump is activated*.
(b) Check the EVAP pressure again when it has stabilized. This pressure is the 0.02 inch leak pressure
standard.
*: The vacuum pump begins to operate as step 1/5 is proceeded to step 2/5.
Result:
DTCs*Test ResultsSuspected Trouble AreasProceed To
'EVAP pressure in step (b) between ±4.85 kPa
and ±1.06 kPa (±36.38 mmHg and ±7.95 mmHg)Not yet determinedA
P043F and P2401EVAP pressure in step (b) ±1.06 kPa (±7.95
mmHg) or more0.02 inch orifice high±flow
Vacuum pump stuck OFFB
P043EEVAP pressure in step (b) below ±4.85 kPa
(±36.38 mmHg)0.02 inch orifice cloggedC
P2419EVAP pressure in step (a) more than ±1.06 kPa
(±7.95 mmHg)Vent valve stuck closedD
*: The DTCs relating to the EVAP system displayed on a hand±held tester when checking.
B Go to step 11
C Go to step 30
D Go to step 19
A
Page 674 of 4323
A23502
ON
Within 15 minutes
2/5
Vent Valve Stuck open (vent)
3/5
ONON
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
Negative
Steps
(Reference)TimeON: Open
OFF: Closed
OFF: Vent ON: Closed
Leak Pressure First 0.02 inch
Standard
DI±472
± DIAGNOSTICSENGINE
666 Author: Date:
2005 SEQUOIA (RM1146U)
7 Perform EVAP system step 2/5 to 3/5 check.
(a) Check the EVAP pressure increase in step 3/5.
Result:
DTCs*Test ResultsSuspected Trouble AreasProceed To
'
EVAP pressure increases by 0.3 kPa (2.25 mmHg)
or more within 10 seconds of proceeding from step
2/5 to step 3/5
Not yet determinedA
P2420No variation in EVAP pressure despite proceeding
from step 2/5 to step 3/5Vent valve stuck open (vent)B
P0451No variation in EVAP pressure during steps 1/5
through 3/5Pressure sensor malfunction stuckC
*: The DTCs relating to the EVAP system displayed on a hand±held tester when checking.
B Go to step 19.
C Go to step 30.
A
Page 675 of 4323
A23502
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
Leak PressureON: Open
NegativeONON
Steps
(Reference)Within 15 minutesON
First 0.02 inch
3/5
OFF: Closed
OFF: Vent ON: Closed
Time Standard
± DIAGNOSTICSENGINE
DI±473
667 Author: Date:
2005 SEQUOIA (RM1146U)
8 Perform EVAP system step 3/5 check.
(a) Wait until the EVAP pressure change is less than 0.1 kPa (0.75 mmHg) for 30 seconds.
(b) Measure the EVAP pressure and record it.
HINT:
A few minutes are required for the EVAP pressure to become saturated. When there is little fuel in the fuel
tank, it takes up to 12 minutes.
NEXT
Page 676 of 4323

A23504
ON
Purge VSV Stuck Closed
4/5
ONON
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
Negative
Steps
(Reference)TimeON: Open
OFF: Closed
OFF: Vent ON: Closed
OK
10
sec
Leak Pressure First 0.02 inch
Standard
DI±474
± DIAGNOSTICSENGINE
668 Author: Date:
2005 SEQUOIA (RM1146U)
9 Perform EVAP system step 4/5 check.
(a) Check the EVAP pressure in step 4/5.
DTCs*Test ResultsSuspected Trouble AreasProceed To
'
EVAP pressure increases by 0.3 kPa (2.25 mmHg)
or more within 10 seconds of proceeding from step
3/5 to step 4/5
Not yet determinedA
P0441
EVAP pressure increases by 0.3 kPa (2.25 mmHg)
or more within 10 seconds of proceeding from step
3/5 to step 4/5Problems in EVAP hose between pure VSV and
throttle bodyB
P0441
Variation in EVAP pressure is less than 0.3 kPa
(2.25 mmHg) for 10 seconds, after proceeding from
step 3/5 to step 4/5
Purge VSV stuck closedC
*: The DTCs relating to the EVAP system displayed on a hand±held tester when checking.
B Go to step 15.
C Go to step 12.
A
Page 677 of 4323

A23505
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
ON: Open
NegativeONON
Steps
(Reference)
ON
OFF: Closed
OFF: Vent ON: Closed
Time
60
sec
5/5
Leak Pressure First 0.02 inch
Standard
Gross Leak
Small Leak
No Leak
Leak PressureSecond 0.02 inch
Standard x 0.2
± DIAGNOSTICSENGINE
DI±475
669 Author: Date:
2005 SEQUOIA (RM1146U)
10 Perform EVAP system step 5/5 check.
(a) Check the EVAP pressure in step 5/5.
(b) Compare the EVAP pressure in step 3/5 and the second 0.02 inch leak pressure standard (step 5/5).
Result:
DTCs*Test ResultsSuspected Trouble AreasProceed To
'EVAP pressure (step 3/5) lower than the second
0.02 inch leak pressure standard (step 5/5)Not yet determined (no leakage from EVAP system)A
P0441 and
P0455EVAP pressure (step 3/5) higher than [second 0.02
inch leak pressure standard (step 5/5) x 0.2]Purge VSV stuck open
EVAP gross leakB
P0456EVAP pressure (step 3/5) higher than second 0.02
inch leak pressure standard (step 5/5)EVAP small leakB
*: The DTCs relating to the EVAP system displayed on a hand±held tester when checking.
A Go to step 36.
B Go to step 12.
Page 678 of 4323
A23506
ON
0.02 inch Orifice High±flow
3/5
ONON
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
Positive
Negative
Steps
(Reference)TimeON: Open
OFF: Closed
OFF: Vent ON: Closed
Leak Pressure 0.02 inch
Standard
2/5
Vacuum Pump Stuck OFF
Within 15 minutes
DI±476
± DIAGNOSTICSENGINE
670 Author: Date:
2005 SEQUOIA (RM1146U)
11 Perform EVAP system step 3/5 check.
(a) Check the EVAP pressure in step 3/5.
Result:
DTCs*Test ResultsSuspected Trouble AreasProceed To
'EVAP pressure less than [0.02 inch leak pressure
standard x 0.2]0.02 inch orifice high±flowA
'EVAP pressure more than [0.02 inch leak pressure
standard x 0.2]Vacuum pump stuck OFFB
*: The DTCs relating to the EVAP system displayed on a hand±held tester when checking.
HINT:
The 0.02 inch leak pressure standard is the value determined in step 2/5.
A Go to step 30.
B Go to step 23.
Page 679 of 4323
B17420
HosePurge VSV
± DIAGNOSTICSENGINE
DI±477
671 Author: Date:
2005 SEQUOIA (RM1146U)
12 Perform active test of purge VSV.
PREPARATION:
(a) On the hand±held tester, select the following menu items:
DIAGNOSIS / ENHANCED OBD II/ ACTIVE TEST /
EVAP VSV.
(b) Disconnect the hose (connected to the canister) from the
purge VSV.
(c) Start the engine.
CHECK:
(a) On the tester, turn off the purge VSV (EVAP VSV: OFF).
(b) Use your finger to confirm that the purge VSV has no suc-
tion.
(c) Using the tester, turn on the purge VSV (EVAP VSV: ON).
(d) Use your finger to confirm that the purge VSV has suction.
RESULT:
Test ResultsSuspected Trouble AreasProceed To
No suction when purge VSV turned OFF, and suction applied
when tuned ONPurge VSV normalA
Suction applied when purge VSV turned OFFPurge VSV stuck openB
No suction when purge VSV turned ON
Purge VSV stuck closed
Problems with EVAP hose between purge VSV and throttle
body
C
B Go to step 14.
C Go to step 15.
A
Page 680 of 4323

DI±478
± DIAGNOSTICSENGINE
672 Author: Date:
2005 SEQUOIA (RM1146U)
13 Check fuel tank cap.
CHECK:
(a) Check that the fuel tank cap is correctly installed.
(b) Confirm that the fuel tank cap is tightened until a few click sounds are heard.
HINT:
If an EVAP tester is available, check the fuel tank cap using the tester.
(1) Remove the fuel tank cap and install it onto a fuel tank cap adaptor.
(2) Connect an EVAP tester pump hose to the adaptor, and pressurize to 3.2 to 3.7 kPa (24 to 28
mmHg) using an EVAP tester pump.
(3) Seal the adaptor and wait for 2 minutes.
(4) Check the pressure. If the pressure is 2 kPa (15 mmHg) or more, the fuel tank cap is normal.
(5) Reinstall the fuel tank cap.
PREPARATION:
Test ResultsSuspected Trouble AreasProceed To
Fuel tank cap correctly installed'A
Fuel tank cap loose
Fuel tank cap improperly installed
Defective fuel tank cap
Fuel tank cap does not meet OEM specifications
B
No fuel tank cap'C
A Go to step 29.
B Go to step 27.
C Go to step 28.