Page 1272 of 3115
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 openOpen 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.
Page 1273 of 3115
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.
Page 1274 of 3115
- 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
Page 1275 of 3115
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
Page 1277 of 3115
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
Page 1282 of 3115
A10193
A20058
- DIAGNOSTICSENGINE
DI-233
426 Author: Date:
15 Check for open and short in harness and connector between EFI or ECD relay
and pressure switching valve, and pressure switching valve and ECM (See page
IN-36).
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).
16 Check whether hose close to fuel tank has been modified, and check whether
there are signs of any accident near fuel tank.
CHECK:
Check for cracks, deformation and loose connection of the fol-
lowing parts:
Fuel tank
Fuel tank filler pipe
Hoses and tubes around fuel tank
NG Repair or replace evaporative emission leak
part.
OK
17 Check vacuum hoses between vapor pressure sensor and fuel tank, and char-
coal canister and pressure switching valve.
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 and damage.
NG Repair or replace vacuum hose.
OK
Page 1284 of 3115
A19627A19432
A19637
E2PTNK
Vacuum Disconnect(+)
(-) E5
E9
- DIAGNOSTICSENGINE
DI-235
428 Author: Date:
20 Check voltage between terminals PTNK and E2 of ECM connectors.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals PTNK and E2 of the
ECM connectors at following condition (1) and (2).
(1) Disconnect the vacuum hose from the vapor pres-
sure sensor.
(2) Using the MITYVAC (Hand-Held Vacuum Pump),
apply a vacuum of 4.0 kPa (30 mmHg, 1.18 in.Hg)
to the vapor pressure sensor.
NOTICE:
The vacuum applied to the vapor pressure sensor must be
less than 66.7 kPa (500 mmHg, 19.7 in.Hg).
OK:
Condition (1) Voltage: 2.9 to 3.7 V
Condition (2) Voltage: 0.5 V or less
OK Go to step 22.
NG
21 Check for open and short in harness and connector between vapor pressure
sensor and ECM (See page IN-36).
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).
22 Check fuel tank inlet valve.
NG Replace fuel tank inlet valve.
OK
Page 1287 of 3115
A10193
A20058
DI-238
- DIAGNOSTICSENGINE
431 Author: Date:
5 Check whether hose close to fuel tank has been modified, and check whether
there are signs of any accident near fuel tank or charcoal canister.
CHECK:
Check for cracks, deformation and loose connection of the fol-
lowing parts:
Fuel tank
Charcoal canister
Fuel tank filler pipe
Hoses and tubes around fuel tank and charcoal
canister
NG Repair or replace evaporative emissions leak
part.
OK
6 Check vacuum hoses between vapor pressure sensor and fuel tank, charcoal
canister and pressure switching valve.
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 and damage.
NG Repair or replace vacuum hose.
OK
7 Check hose and tube between fuel tank and charcoal canister.
CHECK:
(a) Check for proper connection of the fuel tank and fuel evap pipe (See page EC-2), fuel evap pipe and
fuel tube under the floor, fuel tube under the floor and charcoal canister.
(b) Check the hose and tube for cracks, hole and damage.
NG Repair or replace hose and tube.
OK
