Toyota Corolla Repair Manual: Monitor description
Dtc p0451, p0452 or p0453 is recorded by the ecm when the vapor pressure sensor malfunctions.
P0451
The ecm senses pressure in the fuel tank using the vapor pressure sensor. The ecm supplies the sensor with a regulated 5 v reference–voltage and the sensor returns a signal voltage between 0.5 V and 4.5 V according to the pressure level in the fuel tank.
When the pressure in the fuel tank is low, the output voltage of the vapor pressure sensor is low. When it is high, the output voltage is high.
For this dtc p0451, the ecm checks for a ”noisy” sensor or a ”stuck” sensor.
The ecm checks for the ”noisy” sensor by monitoring the fuel tank pressures when the vehicle is stationary and there should be little variation in the tank pressure. If the indicated pressure varies beyond specified limits, the ecm will illuminate the mil and a dtc is set.
The ecm checks for the ”stuck” sensor by monitoring the fuel tank pressure for an extended time period.
If the indicated pressure does not change over this period, the ecm will conclude that the fuel tank pressure sensor is malfunctioning. The ecm will illuminate the mil and a dtc is set.
P0452 and p0453
The ecm senses pressure in the fuel tank using the vapor pressure sensor. The ecm supplies the sensor with a regulated 5 v reference–voltage and the sensor returns a signal voltage between 0.5 V and 4.5 V according to the pressure level in the fuel tank.
When the pressure in the fuel tank is low, the output voltage of the vapor pressure sensor is low. When it is high, the output voltage is high.
If the output voltage of the vapor pressure sensor is out of the normal range, the ecm will determine that there is a malfunction in the sensor or sensor circuit.
When pressure indicated by the vapor pressure sensor deviates below –3.999 Kpa (–30 mmhg) or above 1.999 Kpa (15 mmhg), the ecm interprets this as a malfunction in the vapor pressure sensor. The ecm will turn on the mil and a dtc will be set.
Monitor strategy
P0451
P0452 and p0453
Typical enabling conditions
P0451
P0452 and p0453
Typical malfunction thresholds
P0451
P0452 and p0453
Wiring diagram
Refer to dtc no. P0441
Evaporative emission control
system pressure sensor
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 cont ...
Inspection procedure
Hint:
if different dtcs related to different systems that have terminal e2
as the ground terminal are output
simultaneously, terminal e2 may be open.
If dtc p0441 (purge flow), p0446 (vsv f ...
Other materials:
Inspection procedure
1 Check operation(overdrive)
Drive the vehicle after the engine warms up.
check that overdrive on e off occurs by an operation of the o/d
switch on–off.
2 Inspect terminal voltage(od)
Remove the cruise control ecu assy with the connector
still connected.
turn ...
Calibrating the compass
The direction display deviates from
the true direction determined by the earth’s magnetic field. The amount of deviation
varies according to the geographic position of the vehicle.
If you cross over a map boundary shown in illustration, the compass will deviate.
To obtain higher precision or p ...
Using a Bluetooth® Phone
The hands-free system is a function that allows you to use your cellular phone
without touching it.
This system supports Bluetooth®. Bluetooth® is a wireless data system that allows
the cellular phone to wirelessly connect to the hands-free system and make/receive
calls.
Before making a phon ...