2005 TOYOTA AVENSIS diagnostic

A81699
VC
E13ECM Connector
123
A72877
VCC
Manifold Absolute Pressure
Sensor Connector
Wire Harness SideV1
A81699PIM
E2
E13
ECM Connector
123
A72877
VOUT
GND Manifold Absolute Pressure
Sensor Connector
Wire Harness SideV1
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
05±345
AVENSIS REPAIR MANUAL (RM1018E)
4CHECK HARNESS AND CONNECTOR(ECM ± MANIFOLD ABSOLUTE PRESSURE
SENSOR)
(a)Disconnect the E13 ECM connector.
(b)Disconnect the V1 manifold absolute 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 (V1±3)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
VC (E13±18) or VCC (V1±3) ± Body groundNo continuity
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
CHECK AND REPLACE ECM (See page 01±32)
5 CHECK HARNESS AND CONNECTOR(ECM ± MANIFOLD ABSOLUTE PRESSURE SENSOR)
(a) Disconnect the E13 ECM connector.
(b) Disconnect the V1 manifold absolute pressure sensor
connector.
(c) Check for continuity between the wire harness side con- nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
PIM (E13±33) ± VOUT (V1±2)ContinuityE2 (E13±28) ± GND (V1±1)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
PIM (E13±33) or VOUT (V1±2) ± Body groundNo continuity

05±346
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR


 
AB B+
Power Transistor
Platinum Hot Wire
(Heater)
Output
Voltage
Temperature
sensor
Platinum Hot Wire (Heater)
Temperature sensor

 
AB B+
Power Transistor
Platinum Hot Wire
(Heater)
Output
Voltage
Temperature
sensor
Platinum Hot Wire (Heater)
Temperature sensor

 
AB B+
Power Transistor
Platinum Hot Wire
(Heater)
Output
Voltage
Temperature
sensor
Platinum Hot Wire (Heater)
Temperature sensor
A53295
05±336
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0100 MASS OR VOLUME AIR FLOW CIRCUIT
DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT
LOW INPUT
DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT
HIGH INPUT
CIRCUIT DESCRIPTION
The mass air flow meter uses a platinum hot wire. The hot wire mass air flow meter consists of a platinum
hot wire, a temperature sensor and a control circuit installed in a plastic housing. The hot wire mass air flow
meter works on the principle that the hot wire and temperature sensor located in the intake air bypass of the
housing detect any changes in the intake air temperature.
The hot wire is maintained at the set temperature by controlling the current flow through the hot wire. This
current flow is then measured as the output voltage of the mass air flow meter.
The circuit is constructed so that the platinum hot wire and temperature sensor provide a bridge circuit, with
the power transistor controlled so that the potential of A and B remains equal to maintain the set temperature.

DTC Detection ConditionTrouble Area
P0100Open or short in mass air flow meter circuit with engine speed
4,000 rpm or less for more than 3 seconds.
Ohti ifltiit
P0102Open in mass air flow meter circuit with engine speed 4,000
rpm or less for more than 3 seconds.
Open or short in mass air flow meter circuit

Mass air flow meter


ECM
P0103Short in mass air flow meter circuit with engine speed 4,000
rpm or less for more than 3 seconds.
ECM
HINT:
After confirming DTC ºP0100, P0102 or P0103º, use the hand±held tester to confirm the air flow rate from
the ºDIAGNOSIS / OBD/MOBD / DATA LIST / ALLº.
Air flow rate (gm/s)Malfunction
Approximately 0.0
Mass air flow meter power source circuit open

VG circuit open or short
271.0 or more
EVG circuit open
05CJE±01

A76863
B±Y
Battery FL MAINEngine Room R/B No. 4
L±Y EFI Relay
A6
Mass Air Flow MeterMREL
B±G 4B 1
W±BB±W 53
2
1
29
E138
E9ECM
EFI No. 2
EC 4A 1
Engine Room
J/B No. 4 1A 1
B±G 1 2
EFI 1
Engine Room
R/B No. 1 and
Engine Room
J/B No. 14
4
44
4
4
2
1 W±B
B±W
B±WGR
GRIE1 2
EVG 30
E13VG
G 1
3
2 EA113
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
05±337
AVENSIS REPAIR MANUAL (RM1018E)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
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 mal-
function.
1 READ VALUE OF HAND±HELD TESTER(MASS AIR FLOW RATE)
(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 / MAFº and read its value displayed on
the hand±held tester.
Result:
Air flow rate (gm/s)Proceed to
0.0A
271.0 or moreB
1
Mass Air Flow Rate
270.0 (*1)C
*1: The value must be changed when the throttle valve is opened or closed.

A54396
+B (+)
Wire Harness Side
Mass Air Flow Meter Connector
A6
A76903
VG (+) EVG (±)
E13ECM Connector
05±338
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
BGo to step 5
CCHECK FOR INTERMITTENT PROBLEMS
A
2INSPECT MASS AIR FLOW METER(POWER SOURCE)
(a)Disconnect the A6 mass air flow meter connector.
(b)Turn the ignition switch ON.
(c)Measure the voltage between the terminal of the wire har- ness side connector and body ground.
Standard:
Symbols (Terminal No.)Specified condition
+B (A6±1) ± Body ground9 to 14 V
NGGo to step 7
OK
3INSPECT ECM(VG VOLTAGE)
(a)Start the engine.
(b)Measure the voltage between the specified terminals of the E13 ECM connector.
Standard:
Symbols (Terminal No.)ConditionSpecified condition
VG (E13±30) ±
EVG (E13±29)Engine is idling0.5 to 3.0 V
HINT:
The shift position should be P or N and the A/C switch should
be turned OFF.
OKCHECK AND REPLACE ECM (See page 01±32)
NG

A54396
VG
Wire Harness Side
Mass Air Flow Meter ConnectorE2G
A6
A81699
VG E13ECM Connector
EVG
A76903
EVG
E13ECM Connector
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
05±339
AVENSIS REPAIR MANUAL (RM1018E)
4CHECK HARNESS AND CONNECTOR(ECM ± MASS AIR FLOW METER)
(a)Disconnect the A6 mass air flow meter connector.
(b)Disconnect the E13 ECM connector.
(c)Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
VG (A6±3) ± VG (E13±30)ContinuityE2G (A6±2) ± EVG (E13±29)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
VG (A6±3)or VG (E13±30) ± Body groundNo continuity
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE MASS AIR FLOW METER
5INSPECT ECM(SENSOR GROUND)
(a)Check for continuity between the terminal of the E13 ECM connector and body ground.
Standard:
Symbols (Terminal No.)Specified condition
EVG (E13±29) ± Body groundContinuity
NGCHECK AND REPLACE ECM (See page 01±32)
OK

A54396
VG Wire Harness Side
Mass Air Flow Meter ConnectorE2G A6
A81699
VGE13ECM Connector
EVG
05±340
± DIAGNOSTICSSFI SYSTEM (1AZ±FSE)
AVENSIS REPAIR MANUAL (RM1018E)
6 CHECK HARNESS AND CONNECTOR(ECM ± MASS AIR FLOW METER)
(a) Disconnect the A6 mass air flow meter connector.
(b) Disconnect the E13 ECM connector.
(c) Check for continuity between the wire harness side con-
nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
VG (A6±3) ± VG (E13±30)ContinuityE2G (A6±2) ± EVG (E13±29)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
VG (A6±3) or VG (E13±30) ± Body groundNo continuity
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
REPLACE MASS AIR FLOW METER

A54396
+B
Wire Harness Side
Mass Air Flow Meter Connector
A6
A66053
Engine Room R/B No. 4
EFI Relay
±
DIAGNOSTICS SFI SYSTEM(1AZ±FSE)
05±341
AVENSIS REPAIR MANUAL (RM1018E)
7CHECK HARNESS AND CONNECTOR(EFI RELAY ± MASS AIR FLOW METER)
(a)Inspect the EFI No. 2 fuse.
(1)Remove the EFI No. 2 fuse from the engine room
R/B No. 4.
(2)Check for continuity in the EFI No. 2 fuse.
Standard: Continuity
(b)Disconnect the A6 mass air flow meter connector.
(c)Remove the EFI relay from the engine room R/B No. 4.
(d)Check for continuity between the wire harness side con- nectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
+B (A6±1) ± EFI relay (3)Continuity
Standard (Check for short):
Symbols (Terminal No.)Specified condition
+B (A6±1) or EFI relay (3) ± Body groundNo continuity
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
CHECK FOR ECM POWER SOURCE CIRCUIT (See page 05±502)