Fuel TOYOTA AVENSIS 2005 Service Owners Manual

A76889
FCECM
IB1 Engine Room
R/B No. 1
Engine Room
J/B No. 1
B±G
FL MAIN
BatteryGR
ECW±B 1AE9 10
32 51
1
3 5
4B 1EFI
EFI
Relay
B±G
F25
Fuel
Pump 4
5
W±B 10 Engine
Room
J/B No. 4 1
24 4
4
4 4A 1C8
Circuit
Opening
Relay B±Y
1
2
1
Engine Room
R/B No. 4
BR B±WB±WB±WB±W
L±BG±Y G±Y GR
B±YGR
MREL E98
IE12
6
IC3
± DIAGNOSTICSSFI SYSTEM (1AZ±FE)
05±265
AVENSIS REPAIR MANUAL (RM1018E)
WIRING DIAGRAM

B16200
C8
A18294
FC (+)E1 (±)
ECM Connector
E12E9
05±266
±
DIAGNOSTICS SFI SYSTEM(1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION PROCEDURE
When using hand±held tester:
1PERFORM ACTIVE TEST BY HAND±HELD TESTER(OPERATION OF CIRCUIT OPENING RELAY)
(a)Turn the ignition switch ON.
(b)Select the item ºDIAGNOSIS / OBD/MOBD / ACTIVE TEST / FUEL PUMP / SPD\
º.
(c)Perform the active test with the engine stopped.
Result: The circuit opening relay operates.
OKPROCEED TO NEXT CIRCUIT INSPECTIONSHOWN ON PROBLEM SYMPTOMS TABLE
NG
2CHECK ECM POWER SOURCE CIRCUIT (See page 05±257)
NG REPAIR OR REPLACE POWER SOURCE CIRCUIT
OK
3 INSPECT CIRCUIT OPENING RELAY
(a) Remove the circuit opening relay.
(b) Inspect the circuit opening relay. Standard:
Terminal No.Specified condition
1 ± 2Continuity
No Continuity
3 ± 5Continuity
(Apply battery voltage Terminals 1 and 2)
NG REPLACE CIRCUIT OPENING RELAY
OK
4 INSPECT ECM(CHECK VOLTAGE)
(a) Turn the ignition switch ON.
(b) Measure the voltage between the terminals of the E9 and E12 ECM connector.
Standard:
Symbols (Terminal No.)Specified condition
FC (E9±10) ± E1 (E12±7)8 to 14 V
OK Go to step 6
NG

A66053
Engine Room R/B No.4EFI Relay
123
5
A79099
Wire Harness Side
C8
Circuit Opening Relay Connector
A65748
E9
MRELFC
±
DIAGNOSTICS SFI SYSTEM(1AZ±FE)
05±267
AVENSIS REPAIR MANUAL (RM1018E)
5CHECK HARNESS AND CONNECTOR(EFI RELAY ± CIRCUIT OPENING RELAY,
CIRCUIT OPENING RELAY ± ECM)
(a)Remove the EFI relay from the engine room R/B No.4.
(b)Remove the circuit opening relay.
(c)Disconnect the E9 ECM connector.
(d)Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
EFI relay (3) ± Circuit opening relay (C8±1)
Circuit opening relay (C8±2) ± FC (E9±10)Continuity
EFI relay (1) ± MREL (E9±8)
y
Standard (Check for short):
Symbols (Terminal No.)Specified condition
EFI relay (3) or Circuit opening relay (C8±1) ± Body ground
Circuit opening relay (C8±2) or FC (E9±10) ± Body groundNo continuity
EFI relay (1) or MREL (E9±8) ± Body ground
y
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)
6INSPECT FUEL PUMP ASSY (See page 11±22)
NG REPAIR OR REPLACE FUEL PUMP ASSY
OK

123
5
A79099
Wire Harness Side
C8
Circuit Opening Relay Connector
A66276
Fuel Pump Connector
Wire Harness Side
F25
05±268
±
DIAGNOSTICS SFI SYSTEM(1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
7CHECK HARNESS AND CONNECTOR(CIRCUIT OPENING RELAY ± FUEL PUMP, FUEL PUMP ± BODY GROUND)
(a)Remove the circuit opening relay.
(b)Disconnect the fuel pump connector.
(c)Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
Circuit opening relay (C8±3) ± Fuel pump (F25±4)ContinuityFuel pump (F25±5) ± Body groundContinuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
Circuit opening relay (C8±3) or Fuel pump (F25±4) ±
Body groundNo continuity
NGREPAIR OR REPLACE HARNESS ORCONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)
When not using hand±held tester:
1CHECK OPERATION OF FUEL PUMP (See page 11±19)
OKPROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE
NG
2CHECK ECM POWER SOURCE CIRCUIT (See page 05±257)
NG CHECK FOR ECM POWER SOURCE CIRCUIT
OK

A66053
Engine Room R/B No.4EFI Relay
123
5
A79099
Wire Harness Side
C8
Circuit Opening Relay Connector
A65748
E9
MRELFC
05±270
±
DIAGNOSTICS SFI SYSTEM(1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
5CHECK HARNESS AND CONNECTOR(EFI RELAY ± CIRCUIT OPENING RELAY, CIRCUIT OPENING RELAY ± ECM)
(a)Remove the EFI relay from the engine room R/B No.4.
(b)Remove the circuit opening relay.
(c)Disconnect the E9 ECM connector.
(d)Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
EFI relay (3) ± Circuit opening relay (C8±1)
Circuit opening relay (C8±2) ± FC (E9±10)Continuity
EFI relay (1) ± MREL (E9±8)
y
Standard (Check for short):
Symbols (Terminal No.)Specified condition
EFI relay (3) or Circuit opening relay (C8±1) ± Body ground
Circuit opening relay (C8±2) or FC (E9±10) ± Body groundNo continuity
EFI relay (1) or MREL (E9±8) ± Body ground
y
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)
6INSPECT FUEL PUMP ASSY (See page 11±22)
NG REPAIR OR REPLACE FUEL PUMP ASSY
OK

123
5
A79099
Wire Harness Side
C8
Circuit Opening Relay Connector
A66276
Fuel Pump Connector
Wire Harness Side
F25
±
DIAGNOSTICS SFI SYSTEM(1AZ±FE)
05±271
AVENSIS REPAIR MANUAL (RM1018E)
7CHECK HARNESS AND CONNECTOR(CIRCUIT OPENING RELAY ± FUEL PUMP,
FUEL PUMP ± BODY GROUND)
(a)Remove the circuit opening relay.
(b)Disconnect the fuel pump connector.
(c)Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
Circuit opening relay (C8±3) ± Fuel pump (F25±4)ContinuityFuel pump (F25±5) ± Body groundContinuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
Circuit opening relay (C8±3) or Fuel pump (F25±4) ±
Body groundNo continuity
NGREPAIR OR REPLACE HARNESS ORCONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)

A76869
Engine Room R/B No.1
Engine Room J/B No.1
EFI
12
1 1A1
B±G
4A
4B 11
Engine
Room J/B No.4
B±G
FL MAIN
Battery
EFBR B±Y
IE3
IO1 77
(LHD)(RHD)B±Y3
E9 BATTECM
E1 7
E12
A66054
Engine Room R/B No.1
EFI Fuse
05±262
± DIAGNOSTICSSFI SYSTEM (1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
ECM BACK±UP POWER SOURCE CIRCUIT
CIRCUIT DESCRIPTION
While the ignition switch is OFF, the battery positive voltage is supplied to terminal BATT of the ECM for the
DTCs memory and air±fuel ratio adaptive control value memory, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK FUSE(EFI FUSE)
(a) Remove the EFI fuse from the engine room R/B No.1.
(b) Check for continuity in the EFI fuse.
Standard: Continuity
NG CHECK FOR SHORT IN ALL HARNESSES AND
COMPONENTS CONNECTED FUSE
OK
05C78±01

A73819A±A SectionAirSolid Electrolyte
(Zirconia Element)
Platinum
Electrode Heater
Exhaust Gas
Cover Element
A
A
ECM Monitored
A/F Sensor Voltage
Air±Fuel Ratio
± DIAGNOSTICSSFI SYSTEM (1AZ±FE)
05±249
AVENSIS REPAIR MANUAL (RM1018E)
DTC P2255/28 OXYGEN SENSOR REFERENCE GROUND
CIRCUIT LOW (FOR A/F SENSOR)(BANK 2
SENSOR 1)
DTC P2256/28 OXYGEN SENSOR REFERENCE GROUND
CIRCUIT HIGH (FOR A/F SENSOR)(BANK 2
SENSOR 1)
CIRCUIT DESCRIPTION
HINT:
This DTC is recorded when A/F sensor has a malfunction, although the caption is healed oxygen sensor.
The air±fuel ratio sensor are the lamination type. Compared to the conventional type, the sensor and heater
portions of the lamination type are narrower overall. Because the heat of the heater acts directly on the alumi-
na and zirconia (of the sensor portion) it accelerates the activation of the sensor.
To obtain a high purification rate of 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 A/F sensor has the characteristic that it provides output voltage* being approximately proportional to
the existing air±fuel ratio. The A/F sensor output voltage* is used to provide feedback for the ECM to control
the air±fuel ratio.
By the A/F sensor output, the ECM can determine the deviation amount from the stoichiometric air±fuel ratio
and control the proper injection time immediately. If the A/F sensor is out of order, ECM is unable to perform
the accurate air±fuel ratio control.
The A/F sensor is equipped with 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), the current flows to the
heater to heat the sensor for the accurate oxygen concentration detection.
*: The voltage value changes at the inside of the ECM only.

+25 %
±12.5 %
More than 3.35 V
Less than 3.0 V
Case 1
Case 2
Case 3
Case 4
Output voltage of A/F sensor
(sensor 1)
Injection volume
Output voltage
Output voltage of heated oxygen
sensor (sensor 2)Mainly suspect
trouble area
OK
+25 %
±12.5 %
More than 3.35 V
Less than 3.0V
Injection volume
Output voltage
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
A/F sensor
(A/F sensor, heater, A/F sen-
sor 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


Heated oxygen sensor
(heated oxygen sensor,
heater, heated oxygen sensor
circuit)
± DIAGNOSTICSSFI SYSTEM (1AZ±FE)
05±253
AVENSIS REPAIR MANUAL (RM1018E)
The following procedure of A/F CONTROL enables the technician to check and graph voltage output of both
the A/F sensor and heated oxygen sensor.
For displaying the graph indication, enter ºACTIVE TEST/ A/F CONTROL/USER DATAº, then select ºAFS
B1S1 and O2S B1S2º or ºAFS B2S1 and O2S B2S2º by pressing ºYESº button and push ºENTERº button
before pressing ºF4º button.
HINT:

If DTC   
        is displayed, check bank 1
sensor 1 circuit.

If DTC         
 is displayed, check bank 2
sensor 1 circuit.

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.

A75325
HT
AF+ +B
AF±
Bank 1, Sensor 1 A7
A/F Sensor
A79112
Bank 2, Sensor 1 A8
A/F SensorHT
AF+ +B
AF±
B16200
05±254
± DIAGNOSTICSSFI SYSTEM (1AZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
1 INSPECT AIR FUEL RATIO SENSOR(RESISTANCE OF A/F SENSOR HEATER)
(a) Disconnect the A/F sensor connector.
(b) Measure resistance between terminals HT and +B of the
A/F sensor.
Resistance: 1.8 to 3.4
(20
C)
NG REPLACE AIR FUEL RATIO SENSOR
OK
2 INSPECT A/F RELAY
(a) Remove the A/F sensor heater relay from the engine
room R/B.
(b) Inspect the A/F senor heater relay.
Standard:
Terminal No.Specified condition
1 ± 2Continuity
No Continuity
3 ± 5Continuity
(Apply battery voltage Terminals 1 and 2)
NG REPLACE A/F RELAY
OK