Downloaded from www.Manualslib.com manuals search engine 1A-100 Engine General Information and Diagnosis:
4HO2S-2 ground check
1) Disconnect connector from HO2S-2 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-2 connector at
“RED/BLU”, “BRN”, “ORN” and “BLK/WHT” wire
terminals.
3) If connections are OK, measure resistance between
“ORN” wire terminal of HO2S-2 connector and engine
ground.
Is resistance less than 5
Ω?Go to Step 5. “ORN” wire is open or
high resistance circuit.
Poor “C01-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure resistance between “BRN” wire terminal of
HO2S-2 connector and “C01-11” terminal of ECM
connector.
Is resistance less than 5
Ω?Go to Step 6. “BRN” wire is high
resistance circuit or
open circuit. Poor “C01-
11” terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
6Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “BRN” wire terminal of
HO2S-2 connector and vehicle body ground.
Is resistance infinity?Go to Step 7. “BRN” wire is shorted to
ground circuit.
7HO2S-2 signal circuit check
1) Measure voltage between “BRN” wire terminal of HO2S-
2 connector and vehicle body ground.
Is voltage 0 V?Go to Step 8. “BRN” wire is shorted to
other circuit.
8HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to “DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2)”.
Is circuit in good condition?Go to Step 9. Repair HO2S-2 circuit.
9Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK?Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 10.Repair leakage of
exhaust system.
10Air intake system check
1) Check air intake system for clog or leak.
Is it OK?Replace HO2S-2
referring to “Heated
Oxygen Sensor (HO2S-
1 and HO2S-2)
Removal and
Installation (If Equipped)
in Section 1C”.
Is DTC still exists,
substitute a known-
good ECM and recheck.Repair or replace air
intake system. Step Action Yes No
Downloaded from www.Manualslib.com manuals search engine 1A-102 Engine General Information and Diagnosis:
3Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure resistance between “BRN” wire terminal of
HO2S-2 connector and “C01-11” terminal of ECM
connector.
Is resistance less than 5
Ω?Go to Step 4. “BRN” wire is high
resistance circuit or
open circuit. Poor “C01-
11” terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
4HO2S-2 signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure voltage between “BRN” wire terminal of HO2S-
2 connector and vehicle body ground.
Is voltage 0 V?Go to Step 5. “BRN” wire is shorted to
other circuit.
5HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to “DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2)”.
Is circuit in good condition?Go to Step 6. Repair HO2S-2 circuit. If
circuit is OK, substitute
a known-good ECM and
recheck.
6Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK?Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 8.Repair leakage of
exhaust system.
7Air intake system check
1) Check air intake system for clog or leak.
Is it OK?Replace HO2S-2
referring to “Heated
Oxygen Sensor (HO2S-
1 and HO2S-2)
Removal and
Installation (If Equipped)
in Section 1C”.
If DTC still exists,
substitute a known-
good ECM and recheck.Repair or replace air
intake system. Step Action Yes No
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-103
DTC P0171 / P0172: Fuel System Too Lean / RichS6RW0D1104036
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
WARNING!
• When performing a road test, select a place where there is no traffic or possibility of a traffic
accident and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out by 2 persons, a driver and a tester, on a level road.
NOTE
Check to make sure that following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 °F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature: 70 °C (158 °F) or more
• Altitude (barometric pressure): 2500 m, 8200 ft or less (560 mmHg, 74.4 kPa or more)
1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3) Clear DTC using scan tool.
4) Start engine and warm up to normal operating temperature.
5) Operate vehicle with condition as noted freeze frame data for 5 min.
6) Stop vehicle and check DTC and pending DTC.DTC detecting condition Trouble area
DTC P0171:
Total fuel trim is higher than specified value or short term fuel trim is higher
than specified value for more than 1 min.
(2 driving cycle detection logic)
DTC P0172:
Total fuel trim is lower than specified value or short term fuel trim is lower
than specified value for more than 1 min.
(2 driving cycle detection logic)• Vacuum leakage
• Exhaust gas leakage
• Fuel pressure out of specification
• Fuel injector malfunction
• Heated oxygen sensor-1 malfunction
• MAF sensor malfunction
• ECT sensor malfunction
Downloaded from www.Manualslib.com manuals search engine 1A-174 Engine General Information and Diagnosis:
C01-10 WHTOxygen signal of
heated oxygen
sensor-10 – 1 V Ignition switch turned ON.
— *Deflects between
over 0.5 V and under
0.45 V
(“Reference
waveform No.8: ” and
“Reference waveform
No.9: ”)While engine running at
2,000 r/min. for 1 min. or
longer after warmed up.
C01-11 BRNOxygen signal of
heated oxygen
sensor-2 (if
equipped)4 – 5 V Ignition switch turned ON.
— *Deflects between
over 0.5 V and under
0.45 V
(“Reference
waveform No.10: ”)While engine running at
2,000 r/min. or more after
vehicle running over 30
km/h, 19 mph for 5 min.
C01-12 WHTCAN (low)
communication line
(active low signal)
to TCM (for A/T
model)*0.5 – 2.5 V
(“Reference
waveform No.23: ”)
Ignition switch turned ON
with engine stop.CAN communication line
signal is pulse. Pulse
signal displayed with a
regular frequency which
varies depending on
engine condition. C01-13 REDCAN (high)
communication line
(active high signal)
to TCM (for A/T
model)*2.5 – 4.5 V
(“Reference
waveform No.23: ”)
C01-14GRY/
REDOutput of 5 V
power source for
MAP sensor and A/
C refrigerant
pressure sensor (if
equipped with A/C)4.5 – 5.5 V Ignition switch turned ON. —
C01-15 BLK Ground for ECM Below 0.3 V Ignition switch turned ON. —
C01-16BLU/
REDFuel injector No.3
output10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V
↑↓
10 – 14 V
(“Reference
waveform No.1: ” and
“Reference waveform
No.11: ”)Engine running at idle
after warmed up engine.Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C01-17BLU/
ORNFuel injector No.4
output10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V
↑↓
10 – 14 V
(“Reference
waveform No.1: ” and
“Reference waveform
No.12: ”)Engine running at idle
after warmed up engine.Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C01-18BRN/
YELEGR valve
(stepper motor coil
4) output (if
equipped)10 – 14 V Ignition switch turned ON. —
*0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.4: ”)Ignition switch is turned to
ST (cranking) position.Output signal is active low
duty pulse. Number of
pulse generated times
varies depending on
vehicle condition. Terminal
No.Wire
colorCircuit Normal voltage Condition Remarks
Downloaded from www.Manualslib.com manuals search engine 1A-176 Engine General Information and Diagnosis:
C01-34 — — — — —
C01-35 — — — — —
C01-36 — — — — —
C01-37 — — — — —
C01-38 — — — — —
C01-39 — — — — —
C01-40 WHTThrottle position
sensor (sub) signal1.57 – 1.90 VIgnition switch turned ON
and accelerator pedal at
idle position after warmed
up engine.
—
3.88 – 4.45 V
(“Reference
waveform No.29: ”)Ignition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine.
C01-41 GRYGround for shield
wire of TP sensor
circuitBelow 0.3 V Ignition switch turned ON. —
C01-42 BLKGround for throttle
position sensorBelow 0.3 V Ignition switch turned ON. —
C01-43 REDOutput for 5 V
power source of
throttle position
sensor4.5 – 5.5 V Ignition switch turned ON. —
C01-44 YELOutput of throttle
actuator0 – 1 VIgnition switch turned ON
and accelerator pedal at
idle position after warmed
up engine. Output signal is pulse.
Duty ratio varies
depending on throttle
valve and accelerator
pedal position. *0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.26: ”
and “Reference
waveform No.27: ”)Ignition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine.
C01-45 BLUOutput of throttle
actuator0 – 1 VIgnition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine. Output signal is pulse.
Duty ratio varies
depending on throttle
valve and accelerator
pedal position. *0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.26: ”
and “Reference
waveform No.27: ”)Ignition switch turned ON
and accelerator pedal at
idle position after warmed
up engine.
C01-46BLK/
REDHeater output of
heated oxygen
sensor-110 – 14 V Ignition switch turned ON. —
*0 – 2 V
↑↓
10 – 14 V
(“Reference
waveform No.8: ” and
“Reference waveform
No.9: ”)Engine running at idle
after warmed up engine.Output signal is active low
duty pulse. Duty ratio
varies depending on
engine condition.
C01-47RED/
BLUHeater output of
heated oxygen
sensor-2 (if
equipped)10 – 14 V Ignition switch turned ON.
— 0 – 1 V
(“Reference
waveform No.10: ”)Engine running at idle
after vehicle running over
30 km/h, 19 mph for 5 min. Terminal
No.Wire
colorCircuit Normal voltage Condition Remarks
Downloaded from www.Manualslib.com manuals search engine 1A-184 Engine General Information and Diagnosis:
Reference waveform No.8
Heated oxygen sensor-1 signal (1) with engine idling
Reference waveform No.9
Heated oxygen sensor-1 heater signal (2) with engine
idlingReference waveform No.10
Heated oxygen sensor-2 heater signal (4) with engine
idling
Measurement
terminalCH1: “C01-10” to “C01-57”
CH2: “C01-46” to “C01-58”
Oscilloscope
settingCH1: 500 mV/DIV, CH2: 20 V/DIV
TIME: 1 s/DIV
Measurement
condition• After warmed up to normal
operating temperature
• Engine at specified idle speed
2. Heated oxygen sensor-1 heater signal
Measurement
terminalCH1: “C01-10” to “C01-57”
CH2: “C01-46” to “C01-58”
Oscilloscope
settingCH1: 500 mV/DIV, CH2: 10 V/DIV
TIME: 200 ms/DIV
Measurement
condition• After warmed up to normal
operating temperature
• Engine at specified idle speed
1. Heated oxygen sensor-1 signal 4. ON signal
3. OFF signal 5. One duty cycle
I4RS0B110058-01
I4RS0B110059-01
Measurement
terminalCH1: “C01-11” to “C01-57”
CH2: “C01-47” to “C01-58”
Oscilloscope
settingCH1: 500 mV/DIV, CH2: 10 V/DIV
TIME: 2 s/DIV
Measurement
condition• After warmed up to normal
operating temperature
• Vehicle driving at 60 km/h (37
mph) for 10 min.
• Engine at specified idle speed
1. Heated oxygen sensor-2 signal upper limit
2. Heated oxygen sensor-2 signal lower limit
3. Normal waveform range
I4RS0B110060-01
Downloaded from www.Manualslib.com manuals search engine 1C-8 Engine Electrical Devices:
Heated Oxygen Sensor (HO2S-1 and HO2S-2)
Heater On-Vehicle Inspection (If Equipped)
S6RW0D1306010
1) Disconnect sensor connector.
2) Using ohmmeter, measure resistance between
terminals “V
B” and “GND” of sensor connector.
If found faulty, replace oxygen sensor.
NOTE
Temperature of sensor affects resistance
value largely. Make sure that sensor heater is
at correct temperature.
Resistance of oxygen sensor heater
HO2S-1: 5.0 – 6.4 Ω at 20 °C (68 °F)
HO2S-2: 11.7 – 14.5 Ω at 20 °C (68 °F)
Viewed from terminal side
3) Connect sensor connector securely.
Heated Oxygen Sensor (HO2S-1 and HO2S-2)
Removal and Installation (If Equipped)
S6RW0D1306011
Removal
WARNING!
To avoid danger of being burned, do not
touch exhaust system when system is hot.
Oxygen sensor removal should be performed
when system is cool.
1) Disconnect negative cable at battery.
2) Disconnect connector of heated oxygen sensor and
release its wire harness from clamps.
3) Perform following items before removing heated
oxygen sensor.
a) For HO2S-1, remove exhaust manifold referring
to “Exhaust Manifold Removal and Installation in
Section 1K”, if necessary.
b) For HO2S-2, hoist vehicle.
4) Remove heated oxygen sensor from exhaust pipe or
exhaust manifold.Installation
Reverse removal procedure noting the following.
• Tighten heated oxygen sensor (1) to specified torque.
Tightening torque
Heated oxygen sensor (a): 45 N·m (4.5 kgf-m,
32.5 lb-ft)
• Install exhaust manifold referring to “Exhaust Manifold
Removal and Installation in Section 1K”, if removed.
• Connect connector of heated oxygen sensor (1) and
clamp wire harness securely.
• After installing heated oxygen sensor, start engine
and check that no exhaust gas leakage exists.
[A]: HO2S-1 [B]: HO2S-2
I4RS0A130006-01
[A]: HO2S-1 [B]: HO2S-2
[A]
[B]
1, (a)
1, (a)
I3RM0A130007-01
Downloaded from www.Manualslib.com manuals search engine 1C-14 Engine Electrical Devices:
Specifications
Tightening Torque SpecificationsS6RW0D1307001
Reference:
For the tightening torque of fastener not specified in this section, refer to “Fasteners Information in Section 0A”. Fastening partTightening torque
Note
N⋅mkgf-mlb-ft
ECM mounting bolt 8 0.8 6.0 )
ECT sensor 15 1.5 11.0 )
Heated oxygen sensor 45 4.5 32.5 )
CMP sensor bolt (non-VVT model) 10 1.0 7.5 )
CMP sensor bolt (VVT model) 11 1.1 8.0 )
CKP sensor bolt 11 1.1 8.0 )
Knock sensor 22 2.2 16.0 )
MAF and IAT sensor screw 1.5 0.15 1.1 )