2005 TOYOTA AVENSIS fuel pressure

A14687
(V)
4.5
0.5
(0)019.6
(200)MPa
(kgf/cm2)
Output Voltage
Fuel Pressure
A00309
F16
Fuel Pressure Sensor
18
E13ECM
5V
E1 1 R±W
23
Y±G 2
3
BR28
E2 PRVC
VOUT
GNDE13
E13 VCC 05±406
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0190 FUEL RAIL PRESSURE SENSOR CIRCUIT
CIRCUIT DESCRIPTION
The fuel pressure sensor is installed on a fuel delivery pipe and
detects the fuel pressure. It controls of feedback the pump dis-
charge in order to keep the fuel at target pressure 8 to 13 MPa
(81.6 to 132.6 kgf/cm
2, 1,160 to 1,885 psi) by the ECM.
DTC No.DTC Detection ConditionTrouble Area
P0190Open or short in fuel pressure sensor circuit

Open or short in fuel pressure sensor circuit

Fuel pressure sensor

ECM
HINT:
After confirming DTC ºP0190º, use the hand±held tester to confirm the delivery pipe pressure from ºDIAG-
NOSIS / OBD/MOBD / DATA LIST / ALLº.
Fuel Pressure (MPa)Malfunction
Approximately 0
PR circuit short
19.6 or more

VC circuit open or short

PR circuit open

E2 circuit open
WIRING DIAGRAM
05CKE±01

A59674
F16
VCC (+)
GND (±)
Fuel Pressure Sensor Connector Wire Harness Side
VOUT
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
05±407
AVENSIS REPAIR MANUAL (RM1018E)
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.

Read freeze frame data using the hand±held tester. Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ratio was lean or rich, etc. at
the time of the malfunction.
1 READ VALUE OF HAND±HELD TESTER(FUEL PRESSURE)
(a) Connect the hand±held tester to the DLC3.
(b) Start the engine.
(c) Push the hand±held tester main switch ON.
(d) Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / FUEL PRESSº and read its value dis-
played on the hand±held tester.
Pressure: 8 to 13 MPa (81.6 to 132.6 kgf/cm
2, 1,160 to 1,885 psi)
Result:
Fuel Pressure (MPa)Proceed to
19.6 or moreA
0.0B
OK (8 to 13 MPa (81.6 to 132.6 kgf/cm2, 1,160 to 1,885 psi)) (*1)C
*1: The value must be changed when the engine is run or stopped.
B Go to step 3
C CHECK FOR INTERMITTENT PROBLEMS
A
2 INSPECT FUEL PRESSURE SENSOR(VCC VOLTAGE)
(a) Turn the ignition switch ON.
(b) Measure the voltage between the specified terminals of
the F16 fuel pressure sensor connector.
Standard:
Symbols (Terminal No.)Specified condition
VCC (F16±1) ± GND (F16±3)4.5 to 5.5 V
NG Go to step 4
OK

A76903
PR (+)E2 (±)ECM Connector
E13
A81699
VC
E13
ECM Connector
A59674
F16
VCC GND
Fuel Pressure Sensor Connector
Wire Harness Side
VOUT
05±408
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
3INSPECT ECM(PR VOLTAGE)
(a)Start the engine.
(b)Measure the voltage between the specified terminals of the E13 ECM connector.
Standard:
Symbols (Terminal No.)Specified condition
PR (E13±23) ± E2 (E13±28)2.1 to 3.2 V at 25
C (77
F)
HINT:
The fuel pressure in the delivery pipe is 8 to 13 MPa (81.6 to
132.6 kgf/cm
2, 1,160 to 1,885 psi)
NGGo to step 5
OK
CHECK AND REPLACE ECM (See page 01±32)
4CHECK HARNESS AND CONNECTOR(ECM ± FUEL PRESSURE SENSOR)
(a)Disconnect the E13 ECM connector.
(b)Disconnect the F16 fuel pressure sensor connector.
(c)Check for continuity between the wire harness side con- nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
VC (E13±18) ± VCC (F16±1)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
VC (E13±18) or VCC (F16±1) ± Body groundNo continuity
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)

A81699PRE2
E13
ECM Connector
A59674
F16
GND
Fuel Pressure Sensor Connector Wire Harness Side
VOUT
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
05±409
AVENSIS REPAIR MANUAL (RM1018E)
5 CHECK HARNESS AND CONNECTOR(ECM ± FUEL PRESSURE SENSOR)
(a) Disconnect the E13 ECM connector.
(b) Disconnect the F16 fuel pressure sensor connector.
(c) Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
PR (E13±23) ± VOUT (F16±2)ContinuityE2 (E13±28) ± GND (F16±3)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
PR (E13±23) or VOUT (F16±2) ± Body groundNo continuity
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
REPLACE FUEL PRESSURE SENSOR

05±394
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0171 SYSTEM TOO LEAN (BANK 1)
DTC P0172 SYSTEM TOO RICH (BANK 1)
DTC P0174 SYSTEM TOO LEAN (BANK 2)
DTC P0175 SYSTEM TOO RICH (BANK 2)
CIRCUIT DESCRIPTION
The fuel trim is related to the feedback compensation value, not to the basic injection time. The fuel trim in-
cludes the short±term fuel trim and the long±term fuel trim.
The short±term fuel trim is the short±term fuel compensation used to maintain the air±fuel ratio at stoichio-
metric air±fuel ratio. The signal from the heated oxygen sensor indicates whether the air±fuel ratio is RICH
or LEAN compared to the stoichiometric air±fuel ratio. This variance triggers a reduction in the fuel volume
if the air±fuel ratio is RICH, and an increase in the fuel volume if it is LEAN.
The long±term fuel trim is the overall fuel compensation carried out in long±term to compensate for a continu-
al deviation of the short±term fuel trim from the central value, due to individual engine differences, wear over-
time and changes in the operating environment.
If both the short±term fuel trim and the long±term fuel trim are LEAN or RICH beyond a certain value, it is
detected as a malfunction and the CHK ENG is illuminated.
DTC No.DTC Detection ConditionTrouble Area
P0171
P0174When air±fuel ratio feedback is stable after warming up engine,
fuel trim is considerably in error on LEAN side
(2 trip detection logic)

Air induction system

Injector blockage

Mass air flow meter

Manifold absolute pressure sensor

Engine coolant temperature sensor

Fuel pressure

Gas leakage in exhaust system

Open or short in heated oxygen sensor (bank 1, 2 sensor 1)
circuit

Heated oxygen sensor (bank 1, 2 sensor 1)

Heated oxygen sensor heater (bank 1, 2 sensor 1)

EFI relay

PCV valve and hose

PCV hose connection

ECM
P0172
P0175When air±fuel ratio feedback is stable after warming up engine,
fuel trim is considerably in error on RICH side
(2 trip detection logic)

Injector leakage blockage

Mass air flow meter

Manifold absolute pressure sensor

Engine coolant temperature sensor

Ignition system

Fuel pressure

Gas leakage in exhaust system

Open or short in heated oxygen sensor (bank 1, 2 sensor 1)
circuit

Heated oxygen sensor (bank 1, 2 sensor 1)

ECM
HINT:

When DTC ºP0171 or P0174º is recorded, the actual air±fuel ratio is on the LEAN side. When DTC
ºP0172 or P0175º is recorded, the actual air±fuel ratio is on the RICH side.

If the vehicle runs out of fuel, the air±fuel ratio is LEAN and DTC ºP0171 or P0174º is recorded. The
CHK ENG then comes on.
05CKD±01

+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Case 1
Case 2
Case 3
Case 4
Output voltage of heated oxygen
sensor (sensor 1: front sensor)
Injection volume
Output voltage
Output voltage of heated oxygen
sensor (sensor 2: rear sensor)Mainly suspect
trouble area
OK
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
Sensor 1: front sensor
(sensor 1, heater, sensor 1
circuit)
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NGExtremely rich or lean actual
air±fuel ratio
(Injector, fuel pressure, gas
leakage in exhaust system,
etc.) OK
OK
OK
No reaction
No reaction
No reaction No reaction


Sensor 2: rear sensor
(sensor 2, heater, sensor 2
circuit) 05±396
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
The following A/F CONTROL procedure enables the technician to check and graph the voltage outputs of
both the heated oxygen sensors.
For displaying the graph indication, enter ºACTIVE TEST / A/F CONTROL / USER DATAº, then select ºO2S
B1S1 and O2S B1S2º or ºO2S B2S1 and O2S B2S2º by pressing ºYESº button and push ºENTERº button
before pressing ºF4º button.
HINT:

If different DTCs related to different systems that have terminal E2 as the ground terminal are output
simultaneously, terminal E2 may be open.

Read freeze frame data using the hand±held tester. Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ratio was lean or rich, etc. at
the time of the malfunction.

A high heated oxygen sensor (sensor 1) voltage (0.55 V or more) could be caused by a rich air fuel
mixture. Check for conditions that would cause the engine to run rich.

A low heated oxygen sensor (sensor 1) voltage (0.4 V or less) could be caused by a lean air fuel mix-
ture. Check for conditions that would cause the engine to run lean.




3020
10
5
3
02040
0.1 1
0.3 0.2
0.5 2
6080100
±20
(±4)(104)(140)(176) (32)(68)(212)


30
20
10
5
3
02040
0.1 1
0.3 0.2
0.5 2
6080100
±20
(±4)(104)(140)(176) (32)(68)(212)
A81700
Ohmmeter
Acceptable
TEMPERATURE
C (
F)
RESISTANCE K 
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
05±399
AVENSIS REPAIR MANUAL (RM1018E)
5INSPECT ENGINE COOLANT TEMPERATURE SENSOR(RESISTANCE)
(a)Remove the engine coolant temperature sensor.
(b)Measure the resistance between the terminals.
Resistance:
2.32 to 2.59 k at 20
C (68
F)
0.310 to 0.326 k at 80
C (176
F)
NOTICE:
In case of checking the engine coolant temperature sensor
in the water, be careful not to allow water to go into the ter-
minals. After checking, dry the sensor.
HINT:
Alternate procedure: Connect an ohmmeter to the installed en-
gine coolant temperature sensor and read the resistance. Use
an infrared thermometer to measure the engine temperature in
the immediate vicinity of the sensor. Compare these values to
the resistance/temperature graph. Change the engine temper-
ature (warm up or allow to cool down) and repeat the test.
NGREPLACE ENGINE COOLANT TEMPERATURE SENSOR
OK
6CHECK FOR SPARK AND IGNITION (See page 18±12)
NG REPAIR OR REPLACE
OK
7CHECK FUEL PRESSURE(LOW PRESSURE) (See page 11±33)
NG CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE AND
FILTER
OK
8CHECK FUEL PRESSURE(HIGH PRESSURE) (See page 11±33)
NG CHECK AND REPLACE FUEL PUMP, FUEL PRESSURE SENSOR, WIRING AND FUEL
LEAKAGE
OK

A00798
Atmosphere
Housing
Platinum Electrode
Solid Electrolyte
(Zirconia Element)
Platinum Electrode
Heater
Coating (Ceramic)
Exhaust Gas CoverIdeal Air±Fuel Mixture
Output Voltage
Richer ± Air Fuel Ratio ± Leaner
05±364
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
CIRCUIT DESCRIPTION
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three±way cata-
lytic converter is used. For the most efficient use of the three±way catalytic converter, the air±fuel ratio must
be precisely controlled so that it is always close to the stoichiometric air±fuel ratio.
The heated oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity
of the stoichiometric air±fuel ratio. This is used to detect the oxygen concentration in the exhaust gas and
provide the ECM with feedback control the air±fuel ratio.
When the air±fuel ratio becomes LEAN, the oxygen concentration in the exhaust gas increases. And the
heated oxygen sensor informs the ECM of the LEAN condition (low voltage, i.e. less than 0.45 V).
When the air±fuel ratio is RICHER than the stoichiometric air±fuel ratio, the oxygen will be vanished from
the exhaust gas. And the heated oxygen sensor informs the ECM of the RICH condition (high voltage, i.e.
more than 0.45 V). The ECM judges by the voltage output from the heated oxygen sensor whether the air±
fuel ratio is RICH or LEAN and controls the injection time accordingly. If the malfunction of the heated oxygen
sensor causes an output of abnormal voltage, the ECM becomes unable to perform accurate air±fuel ratio
control.
The heated oxygen sensors include a heater which heats the zirconia element. The heater is controlled by
the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), current flows to the
heater in order to heat the sensor for the accurate oxygen concentration detection.
DTC No.DTC Detection ConditionTrouble Area
P0130
P0150Output voltage of heated oxygen sensor (sensor 1) remains at
0.4 V or more, or 0.55 V or less, during idling after engine is
warmed up (2 trip detection logic)
Open or short in heated oxygen sensor (bank 1, 2 sensor 1)
circuit

Heated oxygen sensor (bank 1, 2 sensor 1)
P2195
P2197Output voltage of heated oxygen sensor (sensor 1) remains at
0.55 V or less, during idling after engine is warmed up (2 trip
detection logic)
Heated oxygen sensor (bank 1, 2 sensor 1)

Heated oxygen sensor heater (bank 1, 2 sensor 1)

EFI relay

Air induction system
P2196
P2198Output voltage of heated oxygen sensor (sensor 1) remains at
0.4 V or more, during idling after engine is warmed up (2 trip
detection logic)
y

Fuel pressure

Injector

ECM
HINT:

Bank 1 refers to the No. 1 and No. 4 cylinders.

Bank 2 refers to the No. 2 and No. 3 cylinders.

Sensor 1 refers to the sensor closest to the engine assembly.

The output voltage of the heated oxygen sensor and the short±term fuel trim value can be read using
the hand±held tester.