Toyota Sienna Service Manual: Evaporative Emission Control System Pressure
DTC P0450 Evaporative Emission Control System Pressure
Sensor / Switch
DTC P0451 Evaporative Emission Control System Pressure
Sensor Range / Performance
DTC P0452 Evaporative Emission Control System Pressure
Sensor / Switch Low Input
DTC P0453 Evaporative Emission Control System Pressure
Sensor / Switch High Input
DTC SUMMARY
HINT:
The canister pressure sensor is built into the canister pump module.
DESCRIPTION
The description can be found in the EVAP (Evaporative Emission) System
MONITOR DESCRIPTION
- DTC P0450: Pressure sensor abnormal voltage fluctuation
If the pressure sensor voltage output rapidly fluctuates between less than
0.45 V and more than 4.9 V,
the ECM interprets this as an open or short circuit malfunction in the
pressure sensor or its circuit, and
stops the EVAP (Evaporative Emission) system monitor. The ECM then
illuminates the MIL and sets
the DTC (1 trip detection logic).
- DTC P0451: Pressure sensor abnormal voltage fluctuation or being
constant
If the pressure sensor voltage output fluctuates rapidly for 10 seconds, the
ECM stops the EVAP
system monitor. The ECM interprets this as the pressure sensor voltage
fluctuating, and stops the
EVAP system monitor. The ECM then illuminates the MIL and sets the DTC.
Alternatively, if the sensor voltage output does not change for 10 seconds,
the ECM interprets this as
the sensor being stuck, and stops the monitor. The ECM then illuminates the
MIL and sets the DTC.
(Both the malfunctions are detected by 2 trip detection logic.)
- DTC P0452: Pressure sensor voltage low
If the pressure sensor voltage output is below 0.45 V, the ECM interprets
this as an open or short circuit
malfunction in the pressure sensor or its circuit, and stops the EVAP system
monitor. The ECM then
illuminates the MIL and sets the DTC (1 trip detection logic).
- DTC P0453: Pressure sensor voltage high
If the pressure sensor voltage output is 4.9 V or more, the ECM interprets
this as an open or short
circuit malfunction in the pressure sensor or its circuit, and stops the
EVAP system monitor. The ECM
then illuminates the MIL and sets the DTC (1 trip detection logic).
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All:
P0451 (Noise monitor):
P0451 (Stuck monitor):
P0450, P0452 and P0453:
TYPICAL MALFUNCTION THRESHOLDS
(a) P0450: Pressure sensor chattering
(b) P0451: Pressure sensor noise
(c) P0451: Pressure sensor stuck
(d) P0452: Pressure sensor low voltage
(e) P0453: Pressure sensor high voltage
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
- When a vehicle is brought into the workshop, leave it as it is. Do
not change the vehicle
condition. For example, do not tighten the fuel cap.
- Do not disassemble the canister pump module.
- The intelligent tester is required to conduct the following
diagnostic troubleshooting
procedure.
1 CONFIRM DTC AND EVAP PRESSURE
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position (do not start
the engine).
- Turn the tester on.
- Select the following menu items: DIAGNOSIS /
ENHANCED OBD II / DTC INFO / CURRENT CODES.
- Read DTCs.
- Select the following menu items: DIAGNOSIS /
ENHANCED OBD II / DATA LIST / EVAP / EVAP VAPOR
PRESS.
- Read the EVAP (Evaporative Emission) pressure
displayed on the tester.
Result
2 CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)
- Turn the ignition switch off.
- Disconnect the E4 ECM connector.
- Measure the resistance between the PPMP terminal of
the ECM connector and the body ground.
Result
- Reconnect the ECM connector.
3 CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)
- Disconnect the C27 canister pump module connector.
- Disconnect the E4 ECM connector.
- Measure the resistance between the PPMP terminal of
the ECM connector and the body ground.
Result
- Reconnect the canister pump module connector.
- Reconnect the ECM connector.
4 CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)
- Disconnect the C27 canister pump module connector.
- Turn the ignition switch to the ON position.
- Measure the voltage and resistance of the canister
connector.
Standard
Result
- Reconnect the canister pump module connector.
5 REPLACE CHARCOAL CANISTER ASSEMBLY
- Replace the canister assembly
NOTICE:
When replacing the canister, check the canister
pump module interior and related pipes for water,
fuel and other liquids. If liquids are present, check
for disconnections and/or cracks in the following: 1)
the pipe from the air inlet port to the canister pump
module; 2) the canister filter; and 3) the fuel tank
vent hose.
6 REPAIR OR REPLACE HARNESS OR CONNECTOR (CANISTER PUMP MODULE - ECM)
HINT:
If the exhaust tailpipe has been removed, go to the next step
before reinstalling it.
7 REPLACE ECM
- Replace the ECM
8 CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position and turn the
tester on.
- Wait for at least 60 seconds.
- On the tester, select the following menu items:
DIAGNOSIS / ENHANCED OBD II / DTC INFO /
PENDING CODES.
HINT:
If no pending DTCs are displayed on the tester, the
repair has been successfully completed.
COMPLETED
DTC P0441 Evaporative Emission Control System Incorrect
Purge Flow
DTC SUMMARY
DESCRIPTION
The circuit description can be found in the EVAP (Evaporative Emission)
System.
INSPECTION PROCEDU ...
DTC P0455 Evaporative Emission Control System Leak
Detected (Gross Leak)
DTC P0456 Evaporative Emission Control System Leak
Detected (Very Small Leak)
DTC SUMMARY
DESCRIPTION
The circuit des ...
Other materials:
Dtc check / clear
1. DTC CHECK (NORMAL MODE)
NOTICE:
When the diagnostic system is switched from the
normal mode to the check mode, all the DTCs and
freeze frame data recorded in the normal mode will
be erased. So before switching modes, always check
the DTCs and freeze frame data, and note the ...
Cleaning and protecting
the vehicle exterior
Perform the following to protect the vehicle and maintain it in
prime condition:
Working from top to bottom, liberally apply water to the vehicle
body, wheel wells and underside of the vehicle to remove any dirt
and dust.
Wash the vehicle body using a sponge or soft cloth, such as a
cha ...
Engine Coolant Temperature Circuit Range / Performance Problem
DESCRIPTION
Refer to DTC P0115 (See page ES-133).
MONITOR DESCRIPTION
The ECT sensor is used to monitor the ECT. The ECT sensor has a built-in
thermistor with a resistance
that varies according to the temperature of the engine coolant. When the ECT
becomes low, the
resistance of the ...