2005 TOYOTA AVENSIS diagnostic

05±38
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
DTCP0116ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM
CIRCUIT DESCRIPTION
Rfer to DTC P0115 on page 05±34
DTC No.DTC Detecting ConditionTrouble Area
P0116
When the temperature of engine coolant is ±7 C (20 F) with
a cold engine, and if the engine coolant temperature sensor

Engine coolant temperature sensorP0116g,g
value is 20 C (68 F) or less even if it has been 20 min or
more since the engine was warmed up. (2 trip detection logic)
g

Thermostat
INSPECTION PROCEDURE
HINT:

Read freeze frame data using \f \b\f\f
 Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for d\
etermining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ra\
tio was lean or rich, etc. at
the time of the malfunction.

If different DTCs that are related to a different systems are output simultaneously while terminal E2
is used as a ground terminal, terminal E2 may be open.
1READ OUTPUT DTC(BESIDES P0116)
(a)Read the DTC using the hand±held tester.
Result:
Display (DTC output)Proceed to
Only ºP0116º is outputA
ºP0116º and other DTCs are outputB
HINT:
If any other codes besides ºP0116º are output, perform the troubleshooting for those DTCs first.
BGO TO RELEVANT DTC CHART
A
2INSPECT THERMOSTAT (See Page 16±3)
NG REPLACE THERMOSTAT
OK
REPLACE ENGINE COOLANT TEMPERATURE SENSOR
05B3R±02

A72925
E2
Engine Coolant Temperature Sensor
2
1B±W
BR
E2 THWECM
19
E13
E13 285V
R 05±34
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0115 ENGINE COOLANT TEMPERATURE CIRCUIT
CIRCUIT DESCRIPTION
A thermistor is built into the engine coolant temperature sensor and changes the resistance value according
to the engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as the ones of the intake air temperature
sensor.
DTC No.DTC Detecting ConditionTrouble Area
P0115Open or short in water temp. sensor circuit

Open or short in Engine coolant temperature sensor circuit

Engine coolant temperature sensor

ECM
If the ECM detects the DTC ºP0115º, it enters the fail±safe mode in which the engine coolant temperature
is assumed to be 80 C (176 F).
HINT:
After confirming DTC P0115, use the hand±held tester to confirm the engine coolant temperature in ºDIAG-
NOSIS / OBD/MOBD / DATA LIST / ALLº.
Temperature DisplayedMalfunction
±40 C (±40 F)Open circuit
140 C (284 F) or moreShort circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:

Read freeze frame data using    
 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.

If different DTCs that are related to a different system are output simultaneously while terminal E2 is
used as a ground terminal, terminal E2 may be open.
05B3Q±02

A75743
ECM
Engine Coolant
Temperature Sensor
A76786
Wire Harness Side
E2
Engine Coolant Temperature
Sensor Connector
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±35
AVENSIS REPAIR MANUAL (RM1018E)
1READ VALUE OF HAND±HELD TESTER(WATER TEMPERATURE)
(a)Connect the hand±held tester to the DLC3.
(b)Turn the ignition switch ON.
(c)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / COOLANT TEMPº and read its value
displayed on the hand±held tester.
Temperature: Same as actual engine coolant temperature
Result:
Temperature DisplayedProceed to
±40 C (±40 F)A
140 C (284 F) or moreB
OK (Same as present temperature)C
HINT:

If there is an open circuit, the hand±held tester indicates ±40
C (±40
F).

If there is a short circuit, the hand±held tester indicates 140
C (284
F) or more.
BGo to step 4
CCHECK FOR INTERMITTENT PROBLEMS (See Page 05±5)
A
2 READ VALUE OF HAND±HELD TESTER(CHECK FOR OPEN IN HARNESS)
(a) Disconnect the engine coolant temperature sensor con- nector.
(b) Connect terminals 1 and 2 of the engine coolant tempera- ture sensor connector.
(c) Turn the ignition switch ON.
(d) Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / COOLANT TEMPº and read its value displayed on
the hand±held tester.
Temperature: 140
C (284
F) or more
OK CONFIRM GOOD CONNECTION AT SENSOR. IF OK, REPLACE ENGINE COOLANT TEMP.
SENSOR
NG

A75742
ECM
Engine Coolant
Temperature Sensor
A18294
THWE2
ECM Connector
E13
A75766
ECM
Engine Coolant
Temperature Sensor
05±36
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
3READ VALUE OF HAND±HELD TESTER(CHECK FOR OPEN IN ECM)
(a)Disconnect the engine coolant temperature sensor con- nector.
(b)Connect terminals THW and E2 of the E13 ECM connec- tor.
HINT:
Before checking, do a visual and contact pressure check for the
ECM connector.
(c)Turn the ignition switch ON.
(d)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / COOLANT TEMPº and read its value displayed on
the hand±held tester.
Temperature: 140
C (284
F) or more
OKREPAIR OR REPLACE HARNESS OR CONNECTOR
NG
CONFIRM GOOD CONNECTION AT ECM. IF OK, CHECK AND REPLACE ECM (See page 01±32)
4 READ VALUE OF HAND±HELD TESTER(CHECK FOR SHORT IN HARNESS)
(a) Disconnect the engine coolant temperature sensor con- nector.
(b) Turn the ignition switch ON.
(c) Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST
/ ALL / COOLANT TEMPº and read its value displayed on
the hand±held tester.
Temperature: ±40
C (±40
F)
OK REPLACE ENGINE COOLANT TEMPERATURE SENSOR
NG

A75744
ECM
Engine Coolant
Temperature Sensor
A65743ECM Connector
E13
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±37
AVENSIS REPAIR MANUAL (RM1018E)
5READ VALUE OF HAND±HELD TESTER(CHECK FOR SHORT IN ECM)
(a)Disconnect the E13 ECM connector.
(b)Disconnect the engine coolant temperature sensor con-
nector.
(c)Turn the ignition switch ON.
(d)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / COOLANT TEMPº and read its value displayed on
the hand±held tester.
Temperature: ±40
C (±40
F)
OKREPAIR OR REPLACE HARNESS OR CONNECTOR
NG
CHECK AND REPLACE ECM (See page 01±32)

(fig. 1)
Acceptable
Resistance k

± 20 0 20 40 60 80 100
(± 4) 32 68 104 140 176 212 30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
Temp.
C (
F)
(fig. 1)
Acceptable
Resistance k

± 20 0 20 40 60 80 100
(± 4) 32 68 104 140 176 212 30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
Temp.
C (
F)
FI4741
05±30
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0110 INTAKE AIR TEMPERATURE CIRCUIT
CIRCUIT DESCRIPTION
The intake air temperature sensor is built into the mass air flow
meter and senses the intake air temperature.
A thermistor built in the sensor changes the resistance value
according to the intake air temperature.
The lower the intake air temperature, the greater the thermistor
resistance value, and the higher the intake air temperature, the
lower the thermistor resistance value (See fig. 1).
The intake air temperature sensor is connected to the ECM
(See below ). The 5 V power source voltage in the ECM is ap-
plied to the intake air temperature sensor from the terminal THA
via resistor R.
That is, the resistor R and the intake air temperature sensor are
connected in series. When the resistance value of the intake air
temperature sensor changes in accordance with changes in the
intake air temperature, the potential at terminal THA also
changes. Based on this signal, the ECM increases the fuel in-
jection volume to improve driveability during cold engine opera-
tion.
DTC No.DTC Detecting ConditionTrouble Area
P0110Open or short in intake air temp. sensor circuit

Open or short in intake air temp. sensor circuit

Intake air temp. sensor (built into mass air flow meter)

ECM
If the ECM detects the DTC ºP0110º, it enters the fail±safe mode in which the intake air temperature is as-
sumed to be 20 C (68 F).
HINT:
After confirming DTC ºP0110º, use the hand±held tester to confirm the intake air temperature from the
ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALLº.
Temperature DisplayedMalfunction
±40 C (±40 F)Open circuit
140 C (284 F) or moreShort circuit
05B3P±02

A72925
A6
Intake Air Temp. Sensor
(built in Mass Air Flow Meter)
4
5 G±R
BR E2
THA ECM
20
E13
E13 28 5V
R
THA
E2
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
05±31
AVENSIS REPAIR MANUAL (RM1018E)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:

Read freeze frame data using \f \b\f\f
 Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, it is useful for d\
etermining whether the vehicle
was running or stopped, the engine was warmed up or not, the air±fuel ra\
tio was lean or rich, etc. at
the time of the malfunction.

If different DTCs that are related to a different system are output simultaneously while terminal E2 is
used as a ground terminal, terminal E2 may be open.
1READ VALUE OF HAND±HELD TESTER(INTAKE AIR TEMPERATURE)
(a)Connect the hand±held tester to the DLC3.
(b)Turn the ignition switch ON.
(c)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / INTAKE AIRº and read its value dis- played on the hand±held tester.
Temperature: The same as actual intake air temperature
Result:
Temperature DisplayedProceed to
±40 C (±40 F)A
140 C (284 F) or moreB
OK (Same as present temperature)C
HINT:

If there is an open circuit, the hand±held tester indicates ±40
C (±40
F).

If there is a short circuit, the hand±held tester indicates 140
C (284
F) or more.
BGo to step 4
CCHECK FOR INTERMITTENT PROBLEMS (See Page 05±5)
A

A75743
Mass Air flow meterECM
A54396
A6
Wire Harness Side
Mass Air Flow Meter Connector E2
THA
A75742
ECM
Mass Air flow meter
A18294
THAE2
ECM Connector
E13
05±32
±
DIAGNOSTICS SFI SYSTEM(1ZZ±FE/3ZZ±FE)
AVENSIS REPAIR MANUAL (RM1018E)
2READ VALUE OF HAND±HELD TESTER(CHECK FOR OPEN IN HARNESS)
(a)Disconnect the mass air flow meter connector.
(b)Connect terminals THA and E2 of the mass air flow meter connector.
(c)Turn the ignition switch ON.
(d)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / INTAKE AIRº and read its value displayed on the
hand±held tester.
Temperature value: 140
C (284
F) or more
OKREPLACE MASS AIR FLOW METER
NG
3READ VALUE OF HAND±HELD TESTER(CHECK FOR OPEN IN ECM)
(a)Disconnect the mass air flow meter connector.
(b)Connect terminals THA and E2 of the E13 ECM connec- tor.
HINT:
Before checking, do a visual and contact pressure check for the
ECM connector.
(c)Turn the ignition switch ON.
(d)Select the item ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALL / INTAKE AIRº and read its value displayed on the
hand±held tester.
Temperature value: 140
C (284
F) or more
NGCHECK AND REPLACE ECM (See page 01±32)
OK
REPAIR OR REPLACE HARNESS OR CONNECTOR