2001 TOYOTA AVALON heater

DI-46
- DIAGNOSTICSENGINE
202 Author
: Date
:
2001 AVALON (RM808U)
3 Check for open and short in harness and connector between ECM and A/F sen-
sor (bank 1, 2 sensor 1) (See page IN-30).
NG Repair or replace harness or connector.
OK
4 Check resistance of A/F sensor heater (bank 1, 2 sensor 1) (See page SF-79).
NG Replace A/F sensor.
OK
5 Check air induction system (See page SF-1).
NG Repair or replace.
OK
6 Check fuel pressure (See page SF-6).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
7 Check injector injection (See page SF-23).
NG Replace injector.
OK

A06104
ON
HTS
(+)
(-)
- DIAGNOSTICSENGINE
DI-51
207 Author
: Date
:
2001 AVALON (RM808U)
DTC P0141 Oxygen Sensor Heater Circuit Malfunction
(Bank 1 Sensor 2)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
P0141
When heater operates, heater current exceeds 2.35 A (2 trip
detection logic)
Open or short in heater circuit of heated oxygen sensor
Htd htP0141Heater current of 0.2 A or less when heater operates (2 trip
detection logic)
Heated oxygen sensor heater

ECM
HINT:

Bank 1 refers to the bank that includes cylinder No.1.

Sensor 2 refers to the sensor farther away from the engine body.
WIRING DIAGRAM
Refer to DTC P0125 on page DI-43.
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the 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 Check voltage between terminal HTS of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF-82).
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal HTS of the ECM con-
nector and body ground.
OK:
Voltage: 9 - 14 V
OK Check and replace ECM (See page IN-30).
NG
2 Check resistance of heated oxygen sensor heater (See page SF-81).
NG Replace heated oxygen sensor.
DI6T3-01

- DIAGNOSTICSENGINE
DI-109
265 Author
: Date
:
2001 AVALON (RM808U)
4 Check resistance of A/F sensor heater (See page SF-79).
NG Replace A/F sensor.
OK
5 Check air induction system (See page SF-1).
NG Repair or replace.
OK
6 Check fuel pressure (See page SF-6).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
7 Check injector injection (See page SF-23).
NG Replace injector.
OK
Replace A/F sensor.
8 Perform confirmation driving pattern (See page DI-106).
Go

DI-1 12
- DIAGNOSTICSENGINE
268 Author
: Date
:
2001 AVALON (RM808U)
HINT:
The voltage of the AFR+ or AFL+ terminal of the ECM is fixed at 3.3 V and the voltage of the AFR- or AFL-
terminal is fixed at 3.0 V. Therefore, it is impossible to check the A/F sensor output voltage at the terminals
(AFR+, AFL+/AFR-, AFL-) of the ECM.
OK:
ConditionA/F Sensor Voltage value
Engine idling
Engine racing
Not remains at 3.30 V (0.660 V*)

Not remains at38V(076V*) or moreDriving at engine speed 1,500 rpm or more and vehicle
speed 40 km/h (25 mph) or more, and operate throttle valve
open and close
Not remains at 3.8 V (0.76 V*) or more

Not remains at 2.8 V (0.56 V*) or less
*: When you use the OBD II scan tool (excluding TOYOTA hand-held tester)
HINT:

During fuel enrichment, there is a case that the output voltage of the A/F sensor is below 2.8 V (0.56
V*), it is normal.

During fuel cut, there is a case that the output voltage of the A/F sensor is above 3.8 V (0.76 V*), it
is normal.

If the output voltage of the A/F sensor remains at 3.30 V (0.660 V*) even after performing all the above
conditions, the A/F sensor circuit may be open.

If the output voltage of the A/F sensor remains at 3.8 V (0.76V*) or more, or 2.8 V (0.56 V*) or less even
after performing all the above conditions, the A/F sensor circuit may be short.
*: When you use the OBD II scan tool (excluding TOYOTA hand-held tester).
OK Go to step 9.
NG
3 Check for open and short in harness and connector between ECM and A/F sen-
sor (See page IN-30).
NG Repair or replace harness or connector.
OK
4 Check resistance of A/F sensor heater (See page SF-79).
NG Replace A/F sensor.
OK

A02032
HAFL ON
HAFR
(+)
(-)
- DIAGNOSTICSENGINE
DI-1 15
271 Author
: Date
:
2001 AVALON (RM808U)
DTC P1135 A/F Sensor Heater Circuit Malfunction (Bank
1 Sensor 1)
DTC P1155 A/F Sensor Heater Circuit Malfunction (Bank
2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0125 on page DI-43.
DTC No.DTC Detecting ConditionTrouble Area
P1135
When the heater operates, heater current exceeds 8 A
(2 trip detection logic)
Open or short in heater circuit of A/F sensor
A/F h tP1135
P1155Heater current of 0.25 A or less when the heater operates
(2 trip detection logic)
A/F sensor heater

ECM
WIRING DIAGRAM
Refer to DTC P0125 on page DI-43.
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the 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 Check voltage between terminals HAFL, HAFR of ECM connector and body
ground.
PREPARATION:
(a) Remove the glove compartment (See page SF-83).
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals HAFL, HAFR of the
ECM connector and body ground.
OK:
Voltage: 9 - 14 V
OK Check and replace ECM (See page IN-30).
NG
2 Check resistance of A/F sensor heater (See page SF-79).
DI2H9-03

DI-1 16
- DIAGNOSTICSENGINE
272 Author
: Date
:
2001 AVALON (RM808U)
NG Replace A/F sensor.
OK
3 Check A/F sensor heater relay (Marking: A/F) (See page SF-61).
NG Replace A/F sensor heater relay.
OK
Check and repair harness or connector between A/F sensor heater relay and A/F sensor, and A/F
sensor and ECM (See page IN-30).

DI07B-20
DI-14
- DIAGNOSTICSENGINE
170 Author
: Date
:
DIAGNOSTIC TROUBLE CODE CHART
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument
or other factors.
If a malfunction code is displayed during the DTC check in check mode, check the circuit for the codes listed
in the table below. For details of each code, turn to the page referred to under the ''See page '' for the respec-
tive ''DTC No.'' in the DTC chart.
SAE CONTROLLED
DTC No.
(See page)Detection ItemTrouble AreaMIL*1Memory
P0100
(DI-23)Mass Air Flow Circuit Malfunc-
tionOpen or short in mass air flow meter circuit
Mass air flow meter
ECM

P0101
(DI-27)Mass Air Flow Circuit Range/
Performance ProblemMass air flow meter
P0110
(DI-28)Intake Air Temp. Circuit Malfunc-
tionOpen or short in intake air temp. sensor circuit
Intake air temp. sensor (built into mass air flow meter)
ECM

P0115
(DI-32)Engine Coolant Temp. Circuit
MalfunctionOpen or short in engine coolant temp. sensor circuit
Engine coolant temp. sensor
ECM

P0116
(DI-36)Engine Coolant Temp. Circuit
Range/Performance ProblemCooling system
Engine coolant temp. sensor
P0120
(DI-38)Throttle/Pedal Position Sensor/
Switch ºAº Circuit MalfunctionOpen or short in throttle position sensor circuit
Throttle position sensor
ECM

P0121
(DI-42)Throttle/Pedal Position Sensor/
Switch ºAº Circuit Range/Perfor-
mance Problem
Throttle position sensor
P0125
(DI-43)Insufficient Coolant Temp. for
Closed Loop Fuel Control
Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
A/F sensor (bank 1, 2 sensor 1)
Air induction system
Fuel pressure
Injector
Gas leakage on exhaust system
ECM

P0128
(DI-48)Thermostat Malfunction
Thermostat
Cooling system
Engine coolant temp. sensor
ECM
P0136
(DI-49)Oxygen Sensor Circuit Malfunc-
tion (Bank 1 Sensor 2)Open or short in heated oxygen sensor circuit
Heated oxygen sensor
P0141
(DI-51)Oxygen Sensor Heater Circuit
Malfunction (Bank 1 Sensor 2)Open or short in heater circuit of heated oxygen sensor
Heated oxygen sensor heater
ECM


- DIAGNOSTICSENGINE
DI-17
173 Author
: Date
:
MANUFACTURER CONTROLLED
DTC No.
(See page)Detection ItemTrouble AreaMIL*Memory
P1130
(DI-106)A/F Sensor Circuit Range/Perfor-
mance Malfunction (Bank 1 Sen-
sor 1)
Open or short in A/F sensor circuit
A/F sensor
Air induction system
Fuel pressure
Injector
ECM

P1133
(DI-1 11)A/F Sensor Circuit Response
Malfunction (Bank 1 Sensor 1)
Open or short in A/F sensor circuit
A/F sensor
Air induction system
Fuel pressure
Injector
ECM

P1135
(DI-1 15)A/F Sensor Heater Circuit Mal-
function (Bank 1 Sensor 1)Open or short in heater circuit of A/F sensor
A/F sensor heater
ECM

P1150
(DI-106)A/F Sensor Circuit Range/Perfor-
mance Malfunction (Bank 2 Sen-
sor 1)
Same as DTC No. P1130
P1153
(DI-1 11)A/F Sensor Circuit Response
Malfunction (Bank 2 Sensor 1)Same as DTC No. P1133
P1155
(DI-1 15)A/F Sensor Heater Circuit Mal-
function (Bank 2 Sensor 1)Same as DTC No. P1135
P1300
(DI-1 17)Igniter Circuit Malfunction (No.1)
Ignition system
Open or short in IGF1 or IGT1 circuit from No.1 ignition coil
with igniter to ECM
No.1 ignition coil with igniter
ECM

P1305
(DI-1 17)Igniter Circuit Malfunction (No.2)
Ignition system
Open or short in IGF2 or IGT2 circuit from No.2 ignition coil
with igniter to ECM
No.2 ignition coil with igniter
ECM

P1310
(DI-1 17)Igniter Circuit Malfunction (No.3)
Ignition system
Open or short in IGF2 or IGT3 circuit from No.3 ignition coil
with igniter to ECM
No.3 ignition coil with igniter
ECM

P1315
(DI-1 17)Igniter Circuit Malfunction (No.4)
Ignition system
Open or short in IGF1 or IGT4 circuit from No.4 ignition coil
with igniter to ECM
No.4 ignition coil with igniter
ECM

P1320
(DI-1 17)Igniter Circuit Malfunction (No.5)
Ignition system
Open or short in IGF2 or IGT5 circuit from No.5 ignition coil
with igniter to ECM
No.5 ignition coil with igniter
ECM

P1325
(DI-1 17)Igniter Circuit Malfunction (No.6)
Ignition system
Open or short in IGF1 or IGT6 circuit from No.6 ignition coil
with igniter to ECM
No.6 ignition coil with igniter
ECM