TOYOTA LAND CRUISER 1998 Factory Repair Manual

A19378A20057
ECM
EVAP VSV
Charcoal Canister
Fuel Tank Fig. 1
(2)
(3) (4) (6)
(8)
(9) (1)
(5)
(7)Vapor Pressure
Sensor
CCVPressure
Switching
Valve
DI-222
- DIAGNOSTICSENGINE
415 Author
: Date
:
DTC P0441 Evaporative Emission Control System Incor-
rect Purge Flow
DTC P0446 Evaporative Emission Control System Vent
Control Circuit
DTC P2418 Evaporative Emission System Valve Control
Circuit/Open
CIRCUIT DESCRIPTION
The vapor pressure sensor, canister closed valve (CCV), and pressure switching valve are used to detect
abnormalities in the evaporative emission control system.
The ECM decides whether there is an abnormality in the evaporative emission control system based on the
vapor pressure sensor signal.
DTCs P0441, P0446 and P2418 are recorded by the ECM when evaporative emissions leak from the compo-
nents within the dotted line in Fig. 1 below, or when there is a malfunction in either the EVAP VSV, the pres-
sure switching valve, or in the vapor pressure sensor itself.
DIC2H-01

A21544
CCV
Pressure Switching Valve
EVAP VSV
Cold Start
ECT/IAT near same temp.Open
ClosedOpen ClosedOpen
Closed
Closed
Closed Open
P0441, P0446,
P0455, P2418
Negative Pressure
OccursP0442, P0456
Tank & Canister
Leak CheckP0446
Pressure Switching
Valve Testing
(ex. Fuel tank cap loose)
(ex. Disconnect of vacuum hose)
P2418
CCV
Testing
Pressure
Switching
valve open
malfunction
(P2418)
(P0455) Gross Leak
P0442
P0456
- DIAGNOSTICSENGINE
DI-223
416 Author
: Date
:
DTC No.DTC Detecting ConditionTrouble Area
P0441
Pressure in charcoal canister and fuel tank does not drop dur-
ing purge control (2 trip detection logic)
Vacuum hose cracks, holed, blocked, damaged or discon-
nected
((1), (2), (3), (4), (5), (6), (7), (8) and (9) in Fig. 1)P0441During purge cut-off, pressure is very low compared with at-
mospheric pressure (2 trip detection logic)
nected ((1), (2), (3), (4), (5), (6), (7), (8) and (9) in Fig. 1)

Fuel tank cap incorrectly installed

Fuel tank cap cracked or damaged
No fuel tank pressure rise when commanding the CCV open
after an EVAP leak test
g

Open or short in vapor pressure sensor circuit

Vapor pressure sensor

Open or short in VSV circuit for EVAPP0446A high negative pressure (vacuum) does not occurs in the
system when commanding the EVAP VSV open and CCV
closed with the pressure switching valve open
Open or short in VSV circuit for EVAP

EVAP VSV

Open or short in VSV circuit for CCV


CCV
No fuel tank pressure change when commanding the pressure
switching valve closed for the check after the EVAP leak test

CCV

Open or short in VSV circuit for pressure switching valve

Pressure switching valve
P2418A high negative pressure (vacuum) does not occurs in the
system when commanding the EVAP VSV open and CCV
closed with the pressure switching valve open
g

Fuel tank cracked, holed or damaged

Charcoal canister cracked, holed or damaged

ECM
HINT:
Typical DTC output of each trouble part
Trouble partTypical DTC output (*1)
Small LeakP0442 and/or P0456
Medium Leak (ex.: Vacuum hose loose)P0455
Large Leak (ex.: Fuel tank cap loose)P0441, P0446, P0455 and P2418
EVAP VSVOpen MalfunctionP0441EVAP VSVClose MalfunctionP0441, P0446, P0455 and P2418
CCVOpen MalfunctionP0441, P0446, P0455 and P2418CCVClose MalfunctionP0446
PSithiVlOpen MalfunctionP2418Pressure Switching ValveClose MalfunctionP0441, P0446, P0455 and P2418
*1: ECM may output some other DTC combination.

DI-224
- DIAGNOSTICSENGINE
417 Author
: Date
:
MONITOR DESCRIPTION
P0441
The ECM checks for a stuck closed malfunction in the EVAP VSV by commanding it to open with the CCV
closed. If a high negative pressure does not develop in the fuel tank, the ECM determines that the EVAP
VSV remains closed. The ECM turns on the MIL and a DTC is set.
The ECM checks for EVAP VSV ºstuck openº fault by commanding both valves (EVAP VSV and CCV) to
close at a time when the fuel tank is at atmospheric pressure. If the fuel tank develops a high negative pres-
sure at this early stage of the test, the ECM determines that the EVAP VSV is stuck OPEN.
The ECM will turn on the MIL and a DTC is set.
P0446
The ECM checks the CCV ºstuck closedº by commanding the CCV to open after the EVAP leak test. If the
fuel tank pressure does not rise (lose vacuum), the ECM determines that the CCV is stuck closed. The ECM
will turn on the MIL and a DTC is set.
If the EVAP VSV ºstuck closedº is detected, the ECM determines that the CCV is ºstuck openº. The ECM
turns on the MIL and a DTC is set.
P2418
The ECM checks the pressure switching valve (bypass VSV) ºstuck openº by commanding the pressure
switching valve to close after the EVAP leak test. If the fuel tank pressure does not change, the ECM deter-
mines that the pressure switching valve is malfunctioning. The ECM will turn on the MIL and a DTC is set.
If the EVAP VSV ºstuck closedº is detected, the ECM determines that the CCV is ºstuck closedº. The ECM
turns on the MIL and a DTC is set.

- DIAGNOSTICSENGINE
DI-225
418 Author
: Date
:
MONITOR STRATEGY
P0441EVAP VSV malfunction
Related DTCsP0446CCV malfunctionRelated DTCs
P2418Bypass VSV malfunction
Required sensors/componentsEVAP VSV, CCV, Bypass VSV and Vapor pressure sensor
Frequency of operationOnce per drive cycle
Duration
P0441 : 90 sec.
P0446 : 10 sec.
P2418 : 10 sec.
MIL operation2 drive cycles
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
Same as P0442 (see page DI-245).
TYPICAL MALFUNCTION THRESHOLDS
P0441
Detection CriteriaThreshold
Either the following condition is met:A or B
A. Following conditions are met:(a) and (b)
(a) Fuel tank pressure at the vacuum introduction start-1.6 kPa (-12 mmHg, -0.47 in.Hg) or more
(b) Difference between the fuel tank pressure at the vacuum
introduction start and completionLess than 0.9 kPa (7 mmHg, 0.27 in.Hg)
B. Following conditions are met:(a) and (b)
(a) Difference between ºminimumº fuel tank pressure before
the leak check and the fuel tank pressure at 14 sec. after
the leak check
0.5 kPa or more (3.5 mmHg, 0.15 in.Hg)
(b) Fuel tank pressure at 14 sec. after the leak checkLess than -3.7 kPa (-28 mmHg, -1.1 in.Hg)
P0446
Case 1: CCV stuck closed
Fuel tank pressure when the CCV is opened after an EVAP
leak checkNot changing
Case 2: CCV stuck open
Fuel tank pressure after the EVAP VSV is opened and man-
ifold vacuum is introduced to the fuel tankNot changing
P2418
Case 1: Bypass VSV stuck open
Fuel tank pressure when the pressure switching valve is
closed after an EVAP leak checkNot changing
Case 2: Bypass VSV stuck closed
Fuel tank pressure after the EVAP VSV is opened and man-
ifold vacuum is introduced to the fuel tankNot changing

DI-226
- DIAGNOSTICSENGINE
419 Author
: Date
:
MONITOR RESULT
The detailed information is described in CHECKING MONITOR STATUSº (see page DI-3).

TID (Test Identification) is assigned to each emission-related component.

TLT (Test Limit Type):
If TLT is 0, the component is malfunctioning when the test value is higher than the test limit.
If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.

CID (Component Identification) is assigned to each test value.

Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.
TID $02: EVAP - Vacuum Monitor
TLTCIDUnit ConversionDescription of Test ValueDescription of Test Limit
1$01Multiply by 0.0916
(mmHg)Test value of EVAP VSV:
Determined by fuel tank pressure change during vacuum introductionMalfunction criterion
1$02Multiply by 0.0458 and
subtract 2.93 (mmHg)Test value of bypass VSV (pressure switching valve):
Determined by fuel tank pressure change at switching over bypass
VSV
Malfunction criterion
0$03Multiply by 0.0458
(mmHg)Test value of 0.04 inch leak:
Determined by fuel tank pressure changeMalfunction criterion
0$04Multiply by 0.0458
(mmHg)Test value of 0.02 inch leak:
Determined by fuel tank pressure changeMalfunction criterion
1$05Multiply by 0.0458 and
subtract 2.93 (mmHg)Test value of CCV:
Determined by fuel tank pressure change at switching over CCVMalfunction criterion

A19970A20087
V1 Vapor Pressure Sensor
Cowl Side J/B LH
Engine Room R/B
Engine Room J/B
F15 FL BlockECM
J/B No. 5
MAIN
BatteryEFI or
ECD No. 2
EFI or ECD RelayJ/B No. 6 J/B No. 5
V4
VSV (EVAP)
MREL CCV
PRG TBP PTNK E2VC
V10 VSV (Pressure
Switching Valve)
VCC
GND
PTNK4
BB1 ID4 Id1 IN2 If1
BB1 ID4 Id1 IN2 If1
BB1 ID4
BD3 BD3 ID4
IX2E5
E5
E5
E5 E9
E9
2A
2K2B 2Q
11
1 11B
1B1A
1CE9
5D5C 6C 6D 5D 5C L-R
3
1
2
BR-W
L-BBR-WL-R L-R L-R L-R L-R
L-B L-BBR BR BR-W BR-W
B-Y L-R L-R L-RLL L B-Y B-Y
SB
SB
B-Y
B-YB-Y B-Y L-B
B-W B-W
B-Y
B-W W-B W-B
B-G
2
EA 7
3
111
14
121
23
13418
28
21
4
27
34 12
1 2 11078 9
45
10
165
15
28
44 43
11 1EFI or ECD No. 1 1221 13
1
2 3
4
B-YL-R
If1 14
V9 VSV (Canister
Closed Valve)
- DIAGNOSTICSENGINE
DI-227
420 Author
: Date
:
WIRING DIAGRAM

DI-228
- DIAGNOSTICSENGINE
421 Author
: Date
:
INSPECTION PROCEDURE
HINT:

If DTC P0441 (Purge Flow), P0446 (CCV) or P2418 (Pressure switching valve) or P0451 (Evaporative
Pressure Sensor) is output with DTC P0442, P0455 or P0456, first troubleshoot DTC P0441, P0446
or P0451. If no malfunction is detected, troubleshoot DTC P0442, P0455 or P0456 next.

Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records
the 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.

When the ENGINE RUN TIME in the freeze frame data is less than 200 seconds, carefully check the
vapor pressure sensor.
Hand-held tester:
1 Check that fuel tank cap meets OEM specifications.
NG Replace with a cap that meets OEM specifica-
tions.
OK
2 Check that fuel tank cap is correctly installed.
NG Correctly install fuel tank cap.
OK
3 Check fuel tank cap (See page EC-5).
NG Replace fuel tank cap.
OK

A19812
VSV is ON
VSV is OFF
- DIAGNOSTICSENGINE
DI-229
422 Author
: Date
:
4 Check filler neck for damage.
PREPARATION:
Remove the fuel tank cap.
CHECK:
Visually inspect the filler neck for damage.
NG Replace filler pipe.
OK
5 Check purge flow.
PREPARATION:
(a) Connect the hand-held tester to the DLC3.
(b) Select the ºENHANCED OBD II / ACTIVE TESTº mode on
the hand-held tester.
(c) Disconnect the vacuum hose for the EVAP VSV from the
charcoal canister.
(d) Start the engine.
(e) Select the item ºEVAP (ALON) / ALLº in the ACTIVE TEST
and operate EVAP VSV.
CHECK:
When the EVAP VSV is operated by the hand-held tester,
check whether the disconnected hose applies suction to your
finger.
OK:
VSV is ON:
Disconnected hose applies suction to your finger.
VSV is OFF:
Disconnected hose applies no suction to your finger.
OK Go to step 9.
NG

DI-230
- DIAGNOSTICSENGINE
423 Author
: Date
:
6 Check vacuum hose between intake manifold and EVAP VSV, and EVAP VSV and
charcoal canister.
CHECK:
(a) Check that the vacuum hose is connected correctly.
(b) Check the vacuum hose for looseness and disconnection.
(c) Check the vacuum hose for cracks, hole, damage and blockage.
NG Repair or replace vacuum hose.
OK
7 Check operation of EVAP VSV (See page SF-44).
NG Replace EVAP VSV.
OK
8 Check for open and short in harness and connector between EFI or ECD relay
and EVAP VSV, and EVAP VSV and ECM (See page IN-36).
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).

A10150A10149BE6653
A10281VSV is OFFVSV is ON ON
Air
FAir
E
F E
- DIAGNOSTICSENGINE
DI-231
424 Author
: Date
:
9 Check CCV.
PREPARATION:
(a) Disconnect the vacuum hose for the CCV VSV from the
charcoal canister.
(b) Turn the ignition switch ON and push the hand-held tes-
ter main switch ON.
(c) Select the ºENHANCED OBD II / ACTIVE TESTº mode on
the hand-held tester.
(d) Select the item ºCAN CTRL VSV / ALLº in the ACTIVE
TEST and operate CCV.
CHECK:
Check the VSV operation when it is operated by the hand-held
tester.
OK:
VSV is ON:
Air does not flow from port E to port F.
VSV is OFF:
Air from port E flows out through port F.
OK Go to step 13.
NG
10 Check vacuum hose between CCV and charcoal canister.
CHECK:
(a) Check that the vacuum hose is connected correctly.
(b) Check the vacuum hose for looseness and disconnection.
(c) Check the vacuum hose for cracks, hole damage, and blockage.
NG Repair or replace vacuum hose.
OK
11 Check operation of CCV (See page SF-48).
NG Replace CCV.
OK