Page 969 of 2267

Component InspectionNCEC0127HEATED OXYGEN SENSOR 1 (B1)NCEC0127S02With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Select ªMANU TRIGº and ªHI SPEEDº in ªDATA MONITORº
mode, and select ªHO2S1 (B1)º and ªHO2S1 MNTR (B1)º.
3) Hold engine speed at 2,000 rpm under no load during the fol-
lowing steps.
4) Touch ªRECORDº on CONSULT-II screen.
5) Check the following.
IªHO2S1 MNTR (B1)º in ªDATA MONITORº mode changes from
ªRICHº to ªLEANº to ªRICHº five times in 10 seconds.
5 times (cycles) are counted as shown below:
R = ªHO2S1 MNTR (B1)º, ªRICHº
L = ªHO2S1 MNTR (B1)º, ªLEANº
IªHO2S1 (B1)º voltage goes above 0.6V at least once.
IªHO2S1 (B1)º voltage goes below 0.3V at least once.
IªHO2S1 (B1)º voltage never exceeds 1.0V.
CAUTION:
Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard surface
such as a concrete floor; use a new one.
Without CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal 62 (Heated oxy-
gen sensor 1 (front) signal) and engine ground.
3) Check the following with engine speed held at 2,000 rpm con-
stant under no load.
IMalfunction indicator goes on more than five times within 10
seconds in Diagnostic Test Mode II (HEATED OXYGEN SEN-
SOR 1 (FRONT) MONITOR).
IThe maximum voltage is over 0.6V at least one time.
IThe minimum voltage is below 0.3V at least one time.
IThe voltage never exceeds 1.0V.
CAUTION:
Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard surface
such as a concrete floor; use a new one.
SEF646Y
SEF647Y
SEF648Y
FR O2 SENSOR
x0.01V-09²99
-02²89
SEF011X
DTC P0133 HEATED OXYGEN SENSOR 1
(FRONT) (RESPONSE MONITORING)SR20DE
Component Inspection
EC-169
Page 970 of 2267

Component DescriptionNCEC0128The heated oxygen sensor 1 (front) is placed into the exhaust
manifold. It detects the amount of oxygen in the exhaust gas com-
pared to the outside air. The heated oxygen sensor 1 (front) has a
closed-end tube made of ceramic zirconia. The zirconia generates
voltage from approximately 1V in richer conditions to 0V in leaner
conditions. The heated oxygen sensor 1 (front) signal is sent to the
ECM. The ECM adjusts the injection pulse duration to achieve the
ideal air-fuel ratio. The ideal air-fuel ratio occurs near the radical
change from 1V to 0V.
CONSULT-II Reference Value in Data Monitor
Mode
NCEC0129Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
IEngine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V+,Approx. 0.6 - 1.0V
HO2S1 MNTR
(B1)LEAN+,RICH
Changes more than 5 times during
10 seconds.
ECM Terminals and Reference ValueNCEC0130Specification data are reference values and are measured between each terminal and 48 (ECM ground).
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
62 RHeated oxygen sensor
1 (front)[Engine is running]
IAfter warming up to normal operating temperature
and engine speed is 2,000 rpm0 - Approximately 1.0V
SEF008W
SEF463R
SEF288D
DTC P0134 HEATED OXYGEN SENSOR 1
(FRONT) (HIGH VOLTAGE)SR20DE
Component Description
EC-170
Page 971 of 2267

On Board Diagnosis LogicNCEC0131To judge the malfunction, the diagnosis checks that the heated
oxygen sensor 1 (front) output is not inordinately high.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0134
0134IAn excessively high voltage from the sensor is sent to
ECM.IHarness or connectors
(The sensor circuit is open or shorted.)
IHeated oxygen sensor 1 (front)
DTC Confirmation ProcedureNCEC0132NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Turn ignition switch ªONº.
4) Select ªDATA MONITORº mode with CONSULT-II.
5) Restart engine and let it idle for 2 minutes.
6) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
SR-173.
With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Restart engine and let it idle for 2 minutes.
4) Turn ignition switch ªOFFº and wait at least 9 seconds.
5) Restart engine and let it idle for 2 minutes.
6) Select ªMODE 3º with GST.
7) If DTC is detected, go to ªDiagnostic Procedureº, EC-SR-173.
IWhen using GST, ªDTC Confirmation Procedureº should
be performed twice as much as when using CONSULT-II or
ECM (Diagnostic Test Mode II) because GST cannot dis-
play MODE 7 (1st trip DTC) concerning this diagnosis.
Therefore, using CONSULT-II or ECM (Diagnostic Test
Mode II) is recommended.
SEF301U
SEF058Y
DTC P0134 HEATED OXYGEN SENSOR 1
(FRONT) (HIGH VOLTAGE)SR20DE
On Board Diagnosis Logic
EC-171
Page 972 of 2267
Wiring DiagramNCEC0133
YEC084A
DTC P0134 HEATED OXYGEN SENSOR 1
(FRONT) (HIGH VOLTAGE)SR20DE
Wiring Diagram
EC-172
Page 973 of 2267

Diagnostic ProcedureNCEC0134
1 RETIGHTEN HEATED OXYGEN SENSOR 1 (FRONT)
Loosen and retighten heated oxygen sensor 1 (front).
Tightening torque:
40-60N×m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)
©GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
SEF207X2. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Check harness continuity between ECM terminal 62 (or terminal 2) and ground.
Continuity should not exist.
4. Also check harness for short to power.
OK or NG
OK©GO TO 3.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
3 CHECK HARNESS CONNECTOR
Check heated oxygen sensor 1 (front) harness connector for water.
Water should not exist.
OK or NG
OK©GO TO 4.
NG©Repair or replace harness connector.
4 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-SR-174.
OK or NG
OK©GO TO 5.
NG©Replace heated oxygen sensor 1 (front).
5 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-SR-114.
©INSPECTION END
Heated oxygen sensor 1
(front) harness connector
Heated oxygen
sensor1 (front)
DTC P0134 HEATED OXYGEN SENSOR 1
(FRONT) (HIGH VOLTAGE)SR20DE
Diagnostic Procedure
EC-173
Page 974 of 2267

Component InspectionNCEC0135HEATED OXYGEN SENSOR 1 (FRONT)NCEC0135S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Select ªMANU TRIGº and ªHI SPEEDº in ªDATA MONITORº
mode, and select ªHO2S1 (B1)º and ªHO2S1 MNTR (B1)º.
3) Hold engine speed at 2,000 rpm under no load during the fol-
lowing steps.
4) Touch ªRECORDº on CONSULT-II screen.
5) Check the following.
IªHO2S1 MNTR (B1)º in ªDATA MONITORº mode changes from
ªRICHº to ªLEANº to ªRICHº five times in 10 seconds.
5 times (cycles) are counted as shown below:
R = ªHO2S1 MNTR (B1)º, ªRICHº
L = ªHO2S1 MNTR (B1)º, ªLEANº
IªHO2S1 (B1)º voltage goes above 0.6V at least once.
IªHO2S1 (B1)º voltage goes below 0.3V at least once.
IªHO2S1 (B1)º voltage never exceeds 1.0V.
CAUTION:
Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard surface
such as a concrete floor; use a new one.
Without CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal 62 (Heated oxy-
gen sensor 1 (front) signal) and engine ground.
3) Check the following with engine speed held at 2,000 rpm con-
stant under no load.
IMalfunction indicator goes on more than five times within 10
seconds in Diagnostic Test Mode II (HEATED OXYGEN SEN-
SOR 1 (FRONT) MONITOR).
IThe maximum voltage is over 0.6V at least one time.
IThe minimum voltage is below 0.3V at least one time.
IThe voltage never exceeds 1.0V.
CAUTION:
Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard surface
such as a concrete floor; use a new one.
SEF646Y
SEF647Y
SEF648Y
FR O2 SENSOR
x0.01V-09²99
-02²89
SEF011X
DTC P0134 HEATED OXYGEN SENSOR 1
(FRONT) (HIGH VOLTAGE)SR20DE
Component Inspection
EC-174
Page 975 of 2267

DescriptionNCEC0136SYSTEM DESCRIPTIONNCEC0136S01
Sensor Input Signal to ECMECM func-
tionActuator
Camshaft position sensor Engine speedHeated oxy-
gen sensor
1 (front)
heater con-
trolHeated oxygen sensor 1 (front)
heater
The ECM performs ON/OFF control of the heated oxygen sensor 1 (front) heater corresponding to the engine
operating condition.
OPERATIONNCEC0136S02
Engine speed Heated oxygen sensor 1 (front) heater
Above 3,200 rpm OFF
More than 20 seconds after exceeding 3,200 rpm ON
CONSULT-II Reference Value in Data Monitor
Mode
NCEC0137Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)IEngine speed: Below 3,200 rpm ON
IMore than 20 seconds after exceeding 3,200 rpm OFF
ECM Terminals and Reference ValueNCEC0138Specification data are reference values and are measured between each terminal and 48 (ECM ground).
TERMI-
NAL NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
4LHeated oxygen sensor 1
(front) heater[Engine is running]
IEngine speed is below 3,200 rpm.Approximately 0V
[Engine is running]
IMore than 20 seconds after exceeding
3,200 rpm.BATTERY VOLTAGE
(11 - 14V)
On Board Diagnosis LogicNCEC0139
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0135
0135IThe current amperage in the heated oxygen sensor 1
(front) heater circuit is out of the normal range.
(An improper voltage drop signal is sent to ECM through
the heated oxygen sensor 1 (front) heater.)IHarness or connectors
(The heated oxygen sensor 1 (front) heater cir-
cuit is open or shorted.)
IHeated oxygen sensor 1 (front) heater
DTC Confirmation ProcedureNCEC0140NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is between 10.5V and 16V at idle.
DTC P0135 HEATED OXYGEN SENSOR 1 (FRONT) HEATERSR20DE
Description
EC-175
Page 976 of 2267
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and run it for at least 5 seconds at idle speed.
3) If 1st trip DTC is detected, go to ªDiagnostic Procedureº, EC-
SR-178.
With GST
1) Start engine and run it for at least 5 seconds at idle speed.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Start engine and run it for at least 5 seconds at idle speed.
4) Select ªMODE 3º with GST.
5) If DTC is detected, go to ªDiagnostic Procedureº, EC-SR-178.
IWhen using GST, ªDTC Confirmation Procedureº should
be performed twice as much as when using CONSULT-II or
ECM (Diagnostic Test Mode II) because GST cannot dis-
play MODE 7 (1st trip DTC) concerning this diagnosis.
Therefore, using CONSULT-II or ECM (Diagnostic Test
Mode II) is recommended.
NEF068A
DTC P0135 HEATED OXYGEN SENSOR 1 (FRONT) HEATERSR20DE
DTC Confirmation Procedure (Cont'd)
EC-176