12–1

EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

EMISSION CONTROL SYSTEM (1NZ–FXE)

120DW–01

LOCATION

Purge Port
Ventilation Valve Assy

Vacuum Switching Valve

Assy No. 2 (EVAP)
Air–fuel Ratio Sensor
Fuel Tank Cap Assy
Heated Oxygen Sensor

Air Inlet Line

Vapor Pressure Charcoal Canister
Sensor Assy Vacuum Switching Valve
(Purge Flow Switching Valve)
Trap w/ Outlet valve
Canister Assy

Charcoal Canister
Filter Assy

VSV for CCV

(Canister Closed Valve)
Purge Line
Charcoal Canister Assy
EVAP Line
A87552

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

Ventilation Valve Assy

Air–fuel Ratio Sensor

Heated Oxygen Sensor

Purge Port
Purge Line
Vacuum Switching Valve
Assy No. 2 ( EVAP)
Charcoal Canister Assy
Roll Over Valve

Charcoal Canister Fuel Tank

Vacuum Switching Valve Cap Assy
(Purge Flow Switching Valve)
Vapor Pressure
Sensor Assy
EVAP Line
Trap w/ Outlet Valve
Charcoal Canister
Canister Assy VSV for CCV Filter Sub–assy
(Canister Closed Valve)
Air Inlet Line

Bladder Tank

A87553

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)
120DX–01

SYSTEM DIAGRAM
The emission control system is determined by the ECM based on signals from various sensors.

ECM

MREL
Vacuum Switching Valve
Assy No. 2 (EVAP)
EVP1

Heated Oxygen Sensor

EFI
+B OX OX1B
Relay
(Shielded)
E HT HT1B

EFI
15 A Air–fuel Ratio Sensor
(Shielded)
+B AFI+ A1A+

HT AFI– A1A–

HA1A
P/I
60 A Vapor Pressure Sensor Assy

PTNK PTNK

VCC VC

E2

E2
MAIN
VSV for CCV
120 A
(Canister Closed Valve)
CCV

TBP
Sub
Charcoal Canister
Battery
Vacuum Switching Valve
(Purge Flow Switching Valve)

A87538

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)
120DY–01

ON–VEHICLE INSPECTION

1. INSPECT AIR–FUEL RATIO SENSOR SYSTEM

E5
(a) Inspect the voltage.
(1) Turn the power switch ON (IG).
(2) Using an voltmeter, measure the voltage between
the ECM terminals.
Standard:
Tester Connection Specified Condition
E5–23 (A1A+) – E5–28 (E1) 3.0 to 3.6 V
E5–22 (A1A–) – E5–28 (E1) 2.7 to 3.3 V
CAUTION:
Connect the test leads from the backside of the connector
with the ECM connector connected.
HINT:
The voltage between the ECM terminals is constant regardless
Voltmeter of the output voltage of the air–fuel ratio sensor.
If the result is not as specified, check the air–fuel ratio sensor
and wire harness.

A88403

(b) Check the output waveform.

Hand–held Tester (1) Set the vehicle to the ”INSPECTION MOD1” (see
page 01–5).
(2) Connect the hand–held tester to the DLC3.
(3) Turn the power switch ON (READY ON).
(4) Turn the hand–held tester ON.
(5) Select the item: DIAGNOSIS / ENHANCED OBD II
/ ENGINE AND ECT / DATA LIST / ALL / AFS B1 S1.
DLC3 A87542 (6) Warm up the air fuel ratio sensor for approximately
2 minutes at 2,500 rpm of the engine speed.
(7) Maintain the engine speed at 2,500 rpm, then check
Keep the Engine Speed
that the waveform of ”AFS B1 S1” is output as illus-
Lean trated.
HINT:
3.3 V 14.7 Air–
The waveform of illustration is a sample.
fuel
Only the hand–held tester shows the waveform of the air
Ratio fuel ratio sensor.
Rich
(8) Check that ”O2S B1 S2” fluctuates between 1 and
Time A86385 0 V with the engine speed at 2,500 rpm.

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

2. INSPECT FUEL CUT OFF RPM

Hand–held Tester (a) Check the operation.
(1) Stat the engine, then warm up.
(2) Connect the hand–held tester to the DLC3.
(3) Turn the hand–held tester ON.
(4) Select the item: DIAGNOSIS / ENHANCED OBD II
/ ENGINE AND ECT / DATA LIST / ALL / INJEC-
TOR.
DLC3 A87542 (5) Drive the vehicle. When releasing the accelerator
pedal after the driving speed is 28 to 37 mph (45 to
60 km/h), read ”INJECTOR” of the hand–held tes-
ter.
Standard: 0 ms

Vacuum Gauge 3. INSPECT EVAP SYSTEM LINE

(a) Set the vehicle to the ”INSPECTION MOD1” (see page
01–5).
(b) Warm up the engine to the normal operating temperature,
then stop the engine.
(c) Connect a vacuum gauge (EVAP control system test
equipment vacuum gauge) to the EVAP service port on
the purge line.
A59499

(d) Connect the hand–held tester to the DLC3.

Hand–held Tester (e) Start the engine.
(f) Turn the hand–held tester ON.
(g) Select the item: DIAGNOSIS / ENHANCED OBD II / EN-
GINE AND ECT / ACTIVE TEST / EVAP VSV / ON.

DLC3 A87542

Vacuum Gauge (h) Check the vacuum at idle.

Vacuum:
Maintain at 0.368 to 19.713 in.Hg (5 to 268 in.Aq) for
over 5 seconds.
If the vacuum does not change, it is suspected that the hose
which connects the VSV for EVAP to the service port is loose
or blocked, or that the VSV is abnormally operating.
(i) Stop the engine.
A59500 (j) Disconnect the hand–held tester from the DLC3.
(k) Disconnect the vacuum gauge (EVAP control system test
equipment vacuum gauge) from the EVAP service port on
the purge line.

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

(l) Connect a pressure gauge to the EVAP service port on

Pressure Gauge
the purge line.

A72589

(m) Inspect the pressure.

(1) Using a hose clipper and similar instrument, clip the
outlet hose No. 1 of the charcoal canister.

A88237

Pressure Gauge (2) Apply pressure (13.5 to 15.5 in.Aq) from the EVAP
service port.
Pressure:
2 minutes after the pressure is added, the gauge
should be over 7.7 to 8.8 in.Aq.
If pressure cannot be applied, it is suspected that the hose
which connects the VSV for purge flow switching valve is loose,
Pressure or that the VSV for purge flow switching valve is open.
A59501

4. INSPECT AIRTIGHTNESS IN FUEL TANK AND FILLER

Hand–held Tester PIPE
(a) Connect the hand–held tester to the DLC3.
(b) Turn the power switch ON (IG).
(c) Turn the hand–held tester ON.
(d) Select the item: DIAGNOSIS / ENHANCED OBD II / EN-
GINE AND ECT / ACTIVE TEST /CAN CTRL VSV / ON.

DLC3 A87542

(e) Connect the pressure gauge to the EVAP service port on

Pressure Gauge
the purge line.
(f) Apply pressure (1.6 kPa (16.3 gf/cm2, 0.23 psi) from the
EVAP service port.
(g) Check that the pressure is maintained for over 30 se-
conds.
(h) Visually check that the fuel tank and fuel tank inlet pipe.

A72589

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EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

(i) Check that the fuel hose and fuel tank inlet pipe are con-
nected.
If there are any defects, replace the fuel tank and fuel tank inlet
pipe.

5. CHECK AIR INLET LINE

(a) Check the ventilation.
(1) Disconnect the ventilation hose
Air
(see page 11–24).
(2) Check that there is ventilation from the charcoal
canister filter to the fuel tank inlet pipe when air is
applied to the vent hose of the charcoal canister fil-
ter.
A88405 If there is no ventilation, replace the charcoal canister filter.
(3) Connect the ventilation hose (see page 11–24).

6. INSPECT VAPOR PRESSURE SENSOR ASSY

(a) Inspect the voltage.
(1) Turn the power switch ON (IG).
(2) Using a voltmeter, measure the voltage between
Voltmeter
the terminals.
Standard:
Tester Connection Specified Condition
1–3 4.5 to 5.5 V
A88404 (3) Remove the fuel tank cap.

(4) Using a voltmeter, measure the voltage between

the terminals.
Standard:
Tester Connection Specified Condition
Voltmeter
2–3 3.0 to 3.6 V
(5) Reinstall the fuel tank cap.
(6) Turn the power switch OFF.

A88235

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12–8
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

7. VISUALLY INSPECT HOSES, CONNECTIONS AND

GASKETS
(a) Check the appearance.
(1) Visually check that there are no cracks, leaks or
damage on the indicated portions in the illustration.
HINT:

Removing the oil level gauge , oil filler cap or ventilation
hoses may cause the engine malfunction or engine stall.
A87597
If the parts between the mass air flow meter and cylinder
head are disconnected, loose or cracked, secondary air
may be sucked. It could cause the engine malfunction or
engine stall.

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 12–9
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)
120DZ–01

INSPECTION

Cylinder Head Side:

1. INSPECT VENTILATION VALVE SUB–ASSY
(a) Check the ventilation.
(1) Install a clean hose to the ventilation valve as il-
lustration.
(2) Check that there is ventilation when air is applied
from the cylinder head side.
CAUTION:
Clean Hose Do not suck the air inside the ventilation valve because it
A59511 is harmful.
If there is no ventilation, replace the ventilation valve.
Intake Manifold Side:
(3) Check that there no ventilation when air is applied
from the intake manifold side.
If there is ventilation, replace the ventilation valve.

Clean Hose

A59512

2. INSPECT VACUUM SWITCHING VALVE ASSY NO.2

(a) Inspect the resistance.
Ohmmeter (1) Using an ohmmeter, measure the resistance be-
tween the terminals.
Standard:
Tester Connection Specified Condition
1–2 26 to 30 Ω at 20C (68F)

If the resistance is not as specified, replace the vacuum switch-

A86290 ing valve No. 2.

(b) Check the ventilation.

Air
(1) Check that there is no ventilation in port F when air
is applied from port E.
If there is ventilation, replace the vacuum switching valve No.
E 2.

A86292

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12–10
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

(2) Apply battery voltage across the terminals.

Air
(3) Check that there is ventilation in port F when air is
applied from port E.
If there is no ventilation, replace the vacuum switching valve
E No. 2.

BatteryA86293

3. INSPECT CHARCOAL CANISTER VACUUM

SWITCHING VALVE
(a) Inspect the resistance.
(1) Using an ohmmeter, measure the resistance be-
Ohmmeter
tween the terminals.
Standard:
Tester Connection Specified Condition
1–2 36 to 42 Ω at 20C (68F)
A87462 1 – Body 10 kΩ or higher
2 – Body 10 kΩ or higher

If the result is not as specified, replace the charcoal canister

vacuum switching valve.

Ohmmeter

Body A87463

Air
(b) Check the ventilation.
(1) Check that there is no ventilation from port E to port
F.
E If there is ventilation, replace the charcoal canister vacuum
F
switching valve.

A87464

(2) Apply battery voltage across the terminals.

(3) Check that there is ventilation in port F when air is
applied from port G.
F If there is no ventilation, replace the charcoal canister vacuum
switching valve.

G
Battery
Air
A87465

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 12–11
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

4. INSPECT TRAP W/OUTLET VALVE CANISTER ASSY

(a) Check the appearance.
(1) Check that there are no cracks or damage on the in-
dicated portion of the trap with outlet valve canister.
If there are any defects, replace the trap with outlet valve canis-
ter.

A87567

(b) Check the ventilation.

(1) Remove the 2 bolts and VSV for CCV (canister
closed valve).

A87516

(2) Check that there is ventilation in port B when air is

applied from port A.
If there is no ventilation, replace the trap with outlet valve canis-
B
ter.

Air A87568

(c) Inspect the VSV for CCV (canister closed valve).

(1) Inspect the resistance.
Using an ohmmeter, measure the resistance be-
Ohmmeter
tween the terminals.
Standard:
Tester Connection Specified Condition
1–2 25 to 30 Ω at 20C (68F)
1–2 32 to 40 Ω at 100C (212F)
A86286 If the resistance is not as specified, replace the trap with outlet
valve canister.
(2) Check the ventilation.
B
Check that there is ventilation in ports B and
C when air is applied from por A.
If there is no ventilation, replace the trap with outlet valve canis-
C
ter.

A Air
A86287

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12–12
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

Apply battery voltage across the terminals.

B
Check that there is no ventilation in port B
when air is applied from port A.
If there is ventilation, replace the trap with outlet valve canister.

Apply battery voltage across the terminals.
C

Check that there is ventilation in port C when
air is applied from port A.
Air If there is no ventilation, replace the trap with outlet valve canis-
A
Battery A86289 ter.

Apply battery voltage across the terminals,

Valve
then check that the valve closed.
If the valve does not close, replace the trap with outlet valve
Closed canister.
(3) Install the VSV for CCV (canister closed valve) with
the 2 bolts.

Battery A86288

5. INSPECT CHARCOAL CANISTER ASSY

(a) Check the appearance.
(1) Check that there are no cracks or damage on the in-
dicated portions of the charcoal canister.
If there are any defects, replace the charcoal canister.

A87562

(b) Check the ventilation.

(1) Disconnect the charcoal canister hose from the
(1)
(2) charcoal canister.
(2) Remove the charcoal canister outlet hose No. 1
from the charcoal canister.

A87563

(3) Check that there is ventilation in port B when air of

4.9 kPa (50 gf/cm2, 0.71 psi)) is applied to port A
C with the port C plugged with your finger.
If there is no ventilation, replace the charcoal canister.

A
A87564

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 12–13
EMISSION CONTROL – EMISSION CONTROL SYSTEM (1NZ–FXE)

(4) Check that there is ventilation in ports B and C when

air (4.9 kPa (50 gf/cm2, 0.71 psi)) is applied to char-
coal canister vent hose.
C
If there is no ventilation, replace the charcoal canister.

A
A87565

6. INSPECT FUEL TANK CAP ASSY

(a) Check tha appearance.
(1) Check that there is no deformation or damage on
the fuel tank cap and gasket.
If there are any defects, replace the fuel tank cap.

Gasket

A91723

7. INSPECT AIR–FUEL RATIO SENSOR

(a) Inspect the resistance.
Ohmmeter (1) Using an ohmmeter, measure the resistance be-
tween the terminals.
Standard:
Tester Connection Specified Condition
1 (HT) – 2 (+B) 1.8 to 3.4 Ω at 20C (68F)
2 (+B) – 4 (AF–) 10 kΩ or higher
A87458 If the result is not as specified, replace the air–fuel ratio sensor.

8. INSPECT HEATED OXYGEN SENSOR

(a) Inspect the resistance.
Ohmmeter (1) Using an ohmmeter, measure the resistance be-
tween the terminals.
Standard:
Tester Connection Specified Condition
1 (HT) – 2 (+B) 11 to 16 Ω at 20C (68F)
1 (HT) – 4 (E) 10 kΩ or higher
A87459 If the result is not as specified, replace the heated oxygen sen-
sor.

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Author: Date: 89
12–14
EMISSION CONTROL – CHARCOAL CANISTER ASSY (1NZ–FXE)

CHARCOAL CANISTER ASSY (1NZ–FXE)

120DV–01

REPLACEMENT
1. DISCHARGE FUEL SYSTEM PRESSURE (See page 11–3)
2. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
3. REMOVE DECK FLOOR BOX REAR (See page 19–2)
4. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
5. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
6. REMOVE REAR SEAT CUSHION ASSY (See page 72–9)
7. REMOVE REAR FLOOR SERVICE HOLE COVER (See page 11–24)
8. REMOVE FLOOR PANEL BRACE FRONT (See page 15–2)
9. REMOVE EXHAUST PIPE ASSY FRONT (See page 11–24)
10. REMOVE FUEL TANK ASSY (See page 11–24)

(c) 11. REMOVE CHARCOAL CANISTER ASSY

(a) Disconnect the VSV connector.
(b) Remove the clamp
(c) Remove the wire harness clamp.
(b)
(a)

A87525

(e) (e) (d) (d) Remove the clamp.

(e) Disconnect the 2 charcoal canister hoses from the fuel
tank retainer and fuel tank to canister tube.
(f) Disconnect the charcoal canister outlet hose No. 1 from
the fuel tank.

(f)
A87524

(g) Remove the bolt and 2 nuts, then remove the charcoal
canister.

A87526

12. INSTALL CHARCOAL CANISTER ASSY

Torque: 6.0 N⋅m (61 kgf⋅cm, 53 in.⋅lbf)
13. INSTALL FUEL TANK ASSY (See page 11–24)
14. INSTALL EXHAUST PIPE ASSY FRONT (See page 11–24)
15. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
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 12–15
EMISSION CONTROL – CHARCOAL CANISTER ASSY (1NZ–FXE)

16. CHECK FOR FUEL LEAKS (See page 11–7)

17. CHECK FOR EXHAUST GAS LEAKS
18. INSTALL FLOOR PANEL BRACE FRONT (See page 15–2)
19. INSTALL INSTRUMENT PANEL FINISH PANEL LOWER CENTER
20. INSTALL REAR FLOOR SERVICE HOLE COVER (See page 11–24)
21. INSTALL REAR SEAT CUSHION ASSY (See page 72–9)
22. INSTALL REAR FLOOR BOARD NO.3
23. INSTALL DECK FLOOR BOX REAR
24. INSTALL REAR FLOOR BOARD NO.2
25. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

2004 Prius – Preliminary Release (RM1075U)

Author: Date: 91
12–16
EMISSION CONTROL – TRAP W/OUTLET VALVE CANISTER ASSY (1NZ–FXE)

TRAP W/OUTLET VALVE CANISTER ASSY (1NZ–FXE)

120DU–01

REPLACEMENT
1. DISCHARGE FUEL SYSTEM PRESSURE (See page 11–3)
2. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
3. REMOVE DECK FLOOR BOX REAR (See page 19–2)
4. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
5. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
6. REMOVE REAR SEAT CUSHION ASSY (See page 72–9)
7. REMOVE REAR FLOOR SERVICE HOLE COVER (See page 11–24)
8. REMOVE FLOOR PANEL BRACE FRONT (See page 15–2)
9. REMOVE EXHAUST PIPE ASSY FRONT (See page 11–24)
10. REMOVE FUEL TANK ASSY (See page 11–24)

(d) 11. REMOVE TRAP W/OUTLET VALVE CANISTER ASSY

(d) (a) Remove the clamp from the fuel tank vent hose and char-
(c)
(a) coal canister hose.
(b) (b) Remove the tube of the fuel tank main tube from the
clamp.
(c) Remove the tube of the fuel tank to canister tube from the
clamp.
(d) Remove the tube of the fuel tank vent hose from the 2 fuel
A87527 tube with grommet clamps No. 1.

(e) Disconnect the VSV connector.

(f) (f) Remove the 2 bolts, then remove the trap with outlet valve
canister and ground terminal of the fuel tank wire.

(f)

(e)

A87528

(g) Remove the gasket from the fuel tank.

A87502

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 12–17
EMISSION CONTROL – TRAP W/OUTLET VALVE CANISTER ASSY (1NZ–FXE)

(h) Remove the 2 clamps from the trap with outlet valve can-
ister.

A87494

(i) Remove the fuel tank vent hose.

(j) Pinch the retainer and pull out the fuel tank vent connec-
tor No. 2 with the fuel tank vent connector No. 2 pushed
to the pipe side to remove the fuel tank vent hose from the
trap with outlet valve canister.
NOTICE:
Pinch

Remove dirt or foreign objects on the fuel tank vent
Pinch
connector No. 2 before this work.
Push A87495
Do not allow any scratches or foreign objects on the
parts when disconnecting as the fuel tank vent con-
Fuel Tank Vent Retainer nector No. 2 has the O–ring that seals the pipe.
Connector No. 2
Perform this work by hand. Do not use any tools.

Do not forcibly bend, twist or turn the nylon tube.

Protect the connected part by covering it with a vinyl
bag after disconnecting the fuel tank vent hose.

If the fuel tank vent connector No. 2 and pipe are
O–ring Pipe stuck, push and pull them to release.
Nylon Tube
A87485

12. INSTALL TRAP W/OUTLET VALVE CANISTER ASSY

(a) Install the fuel tank vent hose.
(1) Align the fuel tank vent connector No. 2 with the
pipe, then push in the fuel tank vent connector No.
2 until the retainer makes a ”click” sound to install
the fuel tank vent hose to the trap with outlet valve
canister.
NOTICE:
Push A87507
Check that there are no scratches or foreign objects
around the connected part of the fuel tank vent con-
nector No. 2 and pipe before this work.

After connecting the fuel tank vent hose, check that
the fuel tank vent hose is securely connected by pull-
ing the fuel tank vent connector No. 2.

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12–18
EMISSION CONTROL – TRAP W/OUTLET VALVE CANISTER ASSY (1NZ–FXE)

(b)
Install a new gasket to the fuel tank.
(c)
While being careful that the gasket does not drop in the
fuel tank, insert the trap with outlet valve canister to the
fuel tank.
(d) Install the trap with outlet valve canister and ground termi-
nal of the fuel tank wire with the 2 bolts.
Torque: 6.0 N⋅m (61 kgf⋅cm, 53 in.⋅lbf)
(e) Install the tube of the fuel tank vent hose to the 2 fuel tube
A87504 with grommet clamps. No. 1.
(f) Install the clamp to the fuel tank vent hose and charcoal
canister hose.
(g) Connect the VSV connector.
(h) Install the fuel tank vent hose to the 2 fuel tube with grom-
met clamps No. 1
(i) Install the tube of the fuel tank to canister tube to the
clamp.
(j) Install the tube of the fuel tank main tube to the clamp.
(k) Install the clamp to the fuel tank vent hose and charcoal
canister hose.
13. INSTALL FUEL TANK ASSY (See page 11–24)
14. INSTALL EXHAUST PIPE ASSY FRONT (See page 11–24)
15. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
16. CHECK FOR FUEL LEAKS (See page 11–7)
17. CHECK FOR EXHAUST GAS LEAKS
18. INSTALL FLOOR PANEL BRACE FRONT (See page 15–2)
19. INSTALL INSTRUMENT PANEL FINISH PANEL LOWER CENTER
20. INSTALL REAR FLOOR SERVICE HOLE COVER (See page 11–24)
21. INSTALL REAR SEAT CUSHION ASSY (See page 72–9)
22. INSTALL REAR FLOOR BOARD NO.3
23. INSTALL DECK FLOOR BOX REAR
24. INSTALL REAR FLOOR BOARD NO.2
25. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

2004 Prius – Preliminary Release (RM1075U)

Author: Date: 94
 EMISSION CONTROL – CHARCOAL CANISTER FILTER 12–19
SUB–ASSY (1NZ–FXE)

CHARCOAL CANISTER FILTER SUB–ASSY (1NZ–FXE)

120DT–01

REPLACEMENT

1. REMOVE FLOOR UNDER COVER NO.1

(a) Remove the 2 clips and 2 bolts, then remove the floor un-
der cover No. 1.

A87521

2. REMOVE CHARCOAL CANISTER FILTER SUB–ASSY

(a) Disconnect the fuel tank vent hose (fuel tank side).
Push
(1) Pinch the retainer and pull out the fuel tank vent
connector No. 2 with the fuel tank vent connector
Pinch No. 2 pushed to the pipe side to disconnect the fuel
tank vent hose from the charcoal canister filter.
Pinch NOTICE:

Remove dirt or foreign objects on the fuel tank vent
A87484 connector No. 2 before this work.

Do not allow any scratches or foreign objects on the
Fuel Tank Vent Retainer parts when disconnecting as the fuel tank vent con-
Connector No. 2 nector No. 2 has the O–ring that seals the pipe.

Perform this work by hand. Do not use any tools.

Do not forcibly bend, twist or turn the nylon tube.

Protect the connected part by covering it with a vinyl
bag after disconnecting the fuel tank vent hose.
O–ring Pipe
If the fuel tank vent connector No. 2 and pipe are
Nylon Tube stuck, push and pull them to release.
A87485

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Author: Date: 95
12–20 EMISSION CONTROL – CHARCOAL CANISTER FILTER
SUB–ASSY (1NZ–FXE)

(b) Disconnect the fuel tank vent hose (fuel tank inlet pipe
side).
Pinch (1) Pinch the retainer and pull out the fuel tank vent
Push
connector No. 2 with the fuel tank vent connector
No. 2 pushed to the pipe side to disconnect the fuel
tank vent hose from the fuel tank inlet pipe.
Pinch NOTICE:

Remove dirt or foreign objects on the fuel tank vent
A87522 connector No. 2 before this work.

Do not allow any scratches or foreign objects on the
Fuel Tank Vent Retainer parts when disconnecting as the fuel tank vent con-
Connector No. 2 nector No. 2 has the O–ring that seals the pipe.

Perform this work by hand. Do not use any tools.

Do not forcibly bend, twist or turn the nylon tube.

Protect the connected part by covering it with a vinyl
bag after disconnecting the fuel tank vent hose.
O–ring Pipe
If the fuel tank vent connector No. 2 and pipe are
Nylon Tube stuck, push and pull them to release.
A87485

(c) Remove the fuel tank suction tube support from the ve-
hicle.
(d)
(d) Remove the bolt, then remove the charcoal canister filter.

(c)

A87523

3. INSTALL CHARCOAL CANISTER FILTER SUB–ASSY

(a) Install the charcoal canister filter with the bolt.
Torque: 34 N⋅m (347 kgf⋅cm, 25 ft⋅lbf)
Push (b) Install the fuel suction tube support to the vehicle.
(c) Connect the fuel tank vent hose (fuel tank inlet pipe side).
(1) Align the fuel tank vent connector No. 2 with the
pipe, then push in the fuel tank vent connector No.
2 until the retainer makes a ”click” sound to connect
A87529 the fuel tank vent hose to fuel tank inlet pipe.
NOTICE:

Check that there are no scratches or foreign objects
around the connected part of the fuel tank vent con-
nector No. 2 and pipe before this work.

After connecting the fuel tank vent hose, check that
the fuel tank vent hose is securely connected by pull-
ing the quick connector.

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 EMISSION CONTROL – CHARCOAL CANISTER FILTER 12–21
SUB–ASSY (1NZ–FXE)

(d)
Connect the fuel tank vent hose (fuel tank side).
Push
(1) Align the fuel tank vent connector No. 2 with the
pipe, then push in the fuel tank vent connector No.
2 until the retainer makes a ”click” sound to connect
the fuel tank vent hose to the charcoal canister filter.
NOTICE:

Check that there are no scratches or foreign objects
around the connected part of the fuel tank vent con-
A87512 nector No. 2 and pipe before this work.

After connecting the fuel tank vent hose, check that
the fuel tank vent hose is securely connected by pull-
ing the quick connector.
4. INSTALL FLOOR UNDER COVER NO.1

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12–22
EMISSION CONTROL – VACUUM SWITCHING VALVE ASSY NO.2 (1NZ–FXE)

VACUUM SWITCHING VALVE ASSY NO.2 (1NZ–FXE)

120DS–01

REPLACEMENT
1. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
2. REMOVE DECK FLOOR BOX REAR (See page 19–2)
3. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
4. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)

5. REMOVE VACUUM SWITCHING VALVE ASSY NO.2

(a) Disconnect the VSV connector.
(b)
(b) Disconnect the 2 fuel vapor feed hoses No. 1 from the
vacuum switching valve No. 2.
(c) (c) Remove the bolt, then remove the vacuum switching
(b)
valve No. 2.

(a)
A87598

6. INSTALL VACUUM SWITCHING VALVE ASSY NO.2

Torque: 7.5 N⋅m (76 kgf⋅cm, 66 in.⋅lbf)
7. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
8. INSTALL REAR FLOOR BOARD NO.3
9. INSTALL DECK FLOOR BOX REAR
10. INSTALL REAR FLOOR BOARD NO.2
11. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

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Author: Date: 98
 EMISSION CONTROL – CHARCOAL CANISTER VACUUM SWITCHING 12–23
VALVE (1NZ–FXE)

CHARCOAL CANISTER VACUUM SWITCHING

VALVE (1NZ–FXE)
120DR–01

REPLACEMENT
1. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
2. REMOVE DECK FLOOR BOX REAR (See page 19–2)
3. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
4. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)

5. REMOVE CHARCOAL CANISTER VACUUM

(a) SWITCHING VALVE
(a) Disconnect the VSV connector.
(b)
(b) Disconnect the 3 charcoal canister hoses from the char-
coal canister vacuum switching valve.

(b)
(b)
A87519

(c) Remove the bolt, then remove the charcoal canister vacu-
um switching valve.

A87520

6. INSTALL CHARCOAL CANISTER VACUUM SWITCHING VALVE

Torque: 2.9 N⋅m (30 kgf⋅cm, 26 in.⋅lbf)
7. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
8. INSTALL REAR FLOOR BOARD NO.3
9. INSTALL DECK FLOOR BOX REAR
10. INSTALL REAR FLOOR BOARD NO.2
11. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

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Author: Date: 99
12–24
EMISSION CONTROL – VAPOR PRESSURE SENSOR ASSY (1NZ–FXE)

VAPOR PRESSURE SENSOR ASSY (1NZ–FXE)

120DQ–01

REPLACEMENT
1. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
2. REMOVE DECK FLOOR BOX REAR (See page 19–2)
3. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
4. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)

5. REMOVE VAPOR PRESSURE SENSOR ASSY

(a) Disconnect the vapor pressure sensor connector.

A88377

(b) Remove the tube joint clip, then pull out the vapor pres-
Pull Out sure sensor from the fuel tank retainer.
NOTICE:

Remove dirt or foreign objects on vapor pressure
sensor before this work.

Do not allow any scratches or foreign objects on the
parts when disconnecting as the vapor pressure sen-
Tube Joint Clip
sor has the O–ring that seals the plug.
A87499
Perform this work by hand. Do not use any tools.

Tube joint
Clip

O–ring
Vapor Pressure
Sensor A89469

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 12–25
EMISSION CONTROL – VAPOR PRESSURE SENSOR ASSY (1NZ–FXE)

6.
INSTALL VAPOR PRESSURE SENSOR ASSY
Push (a)
Push the vapor pressure sensor to the plug of the fuel
tank retainer, then install the tube joint clip.
NOTICE:

Check that there are no scratches or foreign objects
around the connected part of the vapor pressure sen-
sor and fuel tank retainer before this work.

Check that the vapor pressure sensor is securely in-
Tube Joint Clip
A87518 serted to the end.

Check that the tube joint clip is on the collar of the va-
por pressure sensor.

After installing the tube joint clip, check that the vapor
pressure sensor cannot be pulled out.
(b) Connect the vapor pressure sensor connector.
7. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
8. INSTALL REAR FLOOR BOARD NO.3
9. INSTALL DECK FLOOR BOX REAR
10. INSTALL REAR FLOOR BOARD NO.2
11. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

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12–26
EMISSION CONTROL – AIR–FUEL RATIO SENSOR (1NZ–FXE)

AIR–FUEL RATIO SENSOR (1NZ–FXE)

120DO–01

REPLACEMENT
1. PRECAUTION (See page 21–7)
2. REMOVE RADIATOR SUPPORT OPENING COVER (See page 10–15)
3. REMOVE ENGINE UNDER COVER LH
4. REMOVE ENGINE UNDER COVER RH
5. DRAIN HV COOLANT (See page 22–4)
6. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
7. REMOVE DECK FLOOR BOX REAR (See page 19–2)
8. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
9. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
10. REMOVE SERVICE PLUG GRIP (See page 21–116)
11. REMOVE WINDSHIELD WIPER ARM COVER
12. REMOVE FR WIPER ARM RH (See page 66–14)
13. REMOVE FR WIPER ARM LH (See page 66–14)
14. REMOVE HOOD TO COWL TOP SEAL (See page 66–14)
15. REMOVE COWL TOP VENTILATOR LOUVER LH (See page 66–14)
16. REMOVE COWL TOP VENTILATOR LOUVER RH (See page 66–14)
17. REMOVE WINDSHIELD WIPER LINK ASSY (See page 66–14)
18. REMOVE COWL TOP PANEL SUB–ASSY OUTER FRONT (See page 11–15)
19. REMOVE INVERTER COVER (See page 21–23)
20. VERIFY THAT VOLTAGE OF W/CONVERTER INVERTER ASSY IS 0V (See page 21–23)
21. DISCONNECT INVERTER COOLING HOSE NO.2 (See page 21–23)
22. DISCONNECT INVERTER COOLING HOSE NO.1 (See page 21–23)
23. DISCONNECT INVERTER COOLING HOSE NO.6 (See page 21–23)
24. SEPARATE CIRCUIT BREAKER SENSOR NO.1 (See page 21–23)
25. DISCONNECT FRAME WIRE NO.2 (See page 21–23)
26. REMOVE W/CONVERTER INVERTER ASSY (See page 21–23)

27. REMOVE AIR–FUEL RATIO SENSOR

(a) Remove the wire harness clamp from the air–fuel ratio
(b) sensor.
(b) Disconnect the air–fuel ratio sensor connector.
(a)
(c) (c) Using SST, remove the air–fuel ratio sensor.
SST 09224–00010

SST A87473

28. INSTALL AIR–FUEL RATIO SENSOR

(a) Using SST, install the air–fuel ratio sensor.
(b) SST 09224–00010
Torque: 44 N⋅m (450 kgf⋅cm, 33 in.⋅lbf)
(c)
(a) (b) Connect the air–fuel ratio sensor connector.
(c) Install the wire harness clamp to the air–fuel ratio sensor.

SST A87473

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 12–27
EMISSION CONTROL – AIR–FUEL RATIO SENSOR (1NZ–FXE)

29. INSTALL W/CONVERTER INVERTER ASSY (See page 21–23)

30. CONNECT FRAME WIRE NO.2 (See page 21–23)
31. CONNECT CIRCUIT BREAKER SENSOR NO.1 (See page 21–23)
32. CONNECT INVERTER COOLING HOSE NO.6
33. CONNECT INVERTER COOLING HOSE NO.1
34. CONNECT INVERTER COOLING HOSE NO.2
35. INSTALL INVERTER COVER (See page 21–23)
36. INSTALL COWL TOP PANEL SUB–ASSY OUTER FRONT (See page 11–15)
37. INSTALL WINDSHIELD WIPER LINK ASSY (See page 66–14)
38. INSTALL SERVICE PLUG GRIP (See page 21–116)
39. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
40. ADD HV COOLANT (See page 22–4)
41. CHECK FOR HV COOLANT LEAKS (See page 22–1)
42. CHECK FOR EXHAUST GAS LEAKS
43. INSTALL COWL TOP VENTILATOR LOUVER RH
44. INSTALL COWL TOP VENTILATOR LOUVER LH
45. INSTALL HOOD TO COWL TOP SEAL
46. INSTALL FR WIPER ARM LH (See page 66–14)
47. INSTALL FR WIPER ARM RH (See page 66–14)
48. INSTALL WINDSHIELD WIPER ARM COVER
49. INSTALL REAR FLOOR BOARD NO.3
50. INSTALL DECK FLOOR BOX REAR
51. INSTALL REAR FLOOR BOARD NO.2
52. INSTALL ENGINE UNDER COVER RH
53. INSTALL ENGINE UNDER COVER LH
54. INSTALL RADIATOR SUPPORT OPENING COVER
55. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

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Author: Date: 103

12–28
EMISSION CONTROL – HEATED OXYGEN SENSOR (1NZ–FXE)

HEATED OXYGEN SENSOR (1NZ–FXE)

120DP–01

REPLACEMENT
1. REMOVE REAR FLOOR BOARD NO.2 (See page 19–2)
2. REMOVE DECK FLOOR BOX REAR (See page 19–2)
3. REMOVE REAR FLOOR BOARD NO.3 (See page 19–2)
4. DISCONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
5. REMOVE INSTRUMENT PANEL FINISH PANEL LOWER CENTER (See page 71–13)

6. REMOVE HEATED OXYGEN SENSOR

(a) Using a clip remover, remove the clip.
(b) Pull off the floor carpet front.

(b) (a)

A87436

(c) Disconnect the heated oxygen sensor connector.

(d) Remove the grommet of the heated oxygen sensor from
(c) the vehicle.

(d)

A87437

(e) (e) Remove the wire harness clamp bracket from the heated
oxygen sensor.
SST (f) Using SST, remove the heated oxygen sensor.
SST 09224–00010

(f)

A87474

(b) 7. INSTALL HEATED OXYGEN SENSOR

(a) Using SST, install the heated oxygen sensor.
SST SST 09224–00010
Torque: 44 N⋅m (450 kgf⋅cm, 33 in.⋅lbf)
(b) Install the wire harness clamp bracket to the heated oxy-
gen sensor.
(a) (c) Install the grommet of the heated oxygen sensor to the
vehicle.
A87474 (d) Connect the heated oxygen sensor connector.
(e) Install the floor carpet front with the clip.
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 12–29
EMISSION CONTROL – HEATED OXYGEN SENSOR (1NZ–FXE)

8. CONNECT ENGINE WIRE NO.3 (BATTERY NEGATIVE TERMINAL) (See page 19–2)
9. CHECK FOR EXHAUST GAS LEAKS
10. INSTALL INSTRUMENT PANEL FINISH PANEL LOWER CENTER
11. INSTALL REAR FLOOR BOARD NO.3
12. INSTALL DECK FLOOR BOX REAR
13. INSTALL REAR FLOOR BOARD NO.2
14. POWER WINDOW CONTROL SYSTEM INITIALIZE (See page 01–28)

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Author: Date: 105