ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-57
Fig. 1 for Step 3
DTC P0134 HEATED OXYGEN SENSOR (HO2S) CIRCUIT NO ACTIVITY
DETECTED (SENSOR-1)
CIRCUIT DESCRIPTION – Refer to DTC P0130 section.
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Engine warmed up.
While running under other than high load and high
engine speed conditions or at specified idle speed
(engine is in closed loop condition), HO2S-1 output
voltage is high or low continuously.
2 driving cycle detection logic, Continuous
monitoring.“G” or “R” circuit open or short
Heated oxygen sensor malfunction
Fuel system malfunction
Exhaust gas leakage
DTC CONFIRMATION PROCEDURE – Refer to DTC P0130 section.
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Is there DTC(s) other than Fuel system
(DTC P0171 / P0172) and HO2S-1 (DTC P0134)?Go to applicable
DTC Diag. Flow
Table.Go to Step 3.
3Check HO2S-1 and Its Circuit.
1) Connect scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and
keep it at 2000 r / min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator
pedal 5 to 6 times continuously and take foot off from
pedal to enrich and enlean A / F mixture). See Fig. 1.
Does HO2S-1 output voltage deflect between 0.3 V and
over 0.6 V repeatedly?Go to DTC P0171
and P0172 Diag.
Flow Table (Fuel
System Check).Check “R” and “G”
wires for open
and short, and
connections for
poor connection.
If wires and
connections are
OK, replace
HO2S-1.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-59
Fig. 1 for Step 2 Fig. 2 for Step 3
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go t o“ENGINE DIAG.
FLOW TABLE”.
2Check Heater for Operation.
1) Check voltage at terminal C01-7. See Fig. 1.
2) Warm up engine to normal operating temperature.
3) Stop engine.
4) Turn ignition switch ON and Check voltage atIntermittent trouble
Check for intermittent
referring to
“Intermittent and
Poor Connection”Go to Step 3.
terminal C01-7. See Fig. 1. Voltage should be
over 10 V.
5) Start engine, run it at idle and check voltage at the
same terminal. Voltage should be below 1.9 V.
Are check results are specified?in Section 0A.
3Check Heater of Sensor-1.
1) Disconnect HO2S-1 coupler with ignition switch
OFF.
2) Check for proper connection to HO2S-1 at “B/W”
and “Bl” wire terminals.
3) If OK, then check heater resistance. See Fig. 2.
Is it 11.7 – 14.3 Ω at 20C, 68F?“Bl” wire open or
shorted to ground or
poor connection at
C01-7. If wire and
connection are OK,
substitute a
known-good ECM
(PCM) and recheck.Replace HO2S-1.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-61
Usual driving: Driving at 30 – 40 mph, 50 – 60 km/h including short stop according to traffic signal. (under driving condition other than high-load,
high-engine speed, rapid accelerating and decelerating)1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11)and 50 mph
(80 km / h)
Above 20 mph
(32 km / h) Usual driving
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 with 2 persons, a driver and a tester, on a level road.
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for:
–Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Intake air temp.: –10C, 14F or higher
–No exhaust gas leakage and loose connection
2) Warm up engine to normal operating temperature.
3) Drive vehicle under usual driving condition for 5 min. and check HO2S-2 output voltage and “short term fuel
trim” with “Data List” mode on scan tool, and write it down.
4) Stop vehicle (don’t turn ignition switch OFF).
5) Increase vehicle speed to higher than 20 mph, 32 km / h and then stop vehicle.
6) Repeat above steps 5) 4 times.
7) Increase vehicle speed to about 50 mph (80 km / h) in 3rd gear or 2 range.
8) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for 10sec.
or more.
9) Stop vehicle (don’t turn ignition switch OFF) and run engine at idle for 2 min.
After this step 9), if “Oxygen Sensor Monitoring TEST COMPLETED” is displayed in “READINESS TESTS”
mode and DTC is not displayed in “DTC” mode, confirmation test is completed.
If “TEST NOT COMPLTD” is still being displayed, proceed to next step 10).
10) Drive vehicle under usual driving condition for 10 min. (or vehicle is at a stop and run engine at idle for 10 min.
or longer)
11) Stop vehicle (don’t turn ignition switch OFF). Confirm test results according to “Test Result Confirmation Flow
Table” in “DTC CONFIRMATION PROCEDURE” of DTC P0420.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-63
To other sensor
Main
fuseIgnition
switch
Heater
To HO2S-1
heater
DTC P0141 HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT
MALFUNCTION (SENSOR-2)
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC will set when A or B condition it met.
A. Low voltage at terminal C02-4 for specified time after engine
start or while engine running at high load.
B. High voltage at terminal C02-4 while engine running under other
than above condition.
2 driving cycle detection logic, continuous monitoring.HO2S-2 heater circuit open or shorted
to ground
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF once and then ON.
2) Clear DTC, start engine and warm up engine to normal operating temperature.
3) Keep it at 2000 r / min for 2 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
6-1-64 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 2
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check HO2S-2 Heater and Its Circuit.
1) Warm up engine to normal operating temperature.
2) Stop engine.
3) Turn ignition switch ON and check voltage at
terminal C02-4 See Fig. 1. Voltage should be
over 10 V.
4) Start engine, run it at idle and check voltage at the
same terminal after 1 min. from engine start.
Voltage should be below 1.9 V.
Are check result as specified?Intermittent trouble.
Check for intermittent
referring to
“Intermittent and
Poor Connection”
in Section 0A.Go to Step 3.
3Check Heater or Sensor-2.
1) Disconnect HO2S-2 coupler with ignition switch
OFF.
2) Check for proper connection to HO2S-2 at “B/W”
and “Lg / B” wire terminals.
3) If OK, then check heater resistance.
Is it 11.7 – 14.3 Ω at 20C, 68F?“Lg / B” wire open or
shorted to ground or
poor connection at
C02-4. If wire and
connection are OK,
substitute a
known-good ECM
(PCM) and recheck.Replace HO2S-2.
6-1-66 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
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 with 2 persons, a driver and a tester on a level road.
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for:
–Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Intake air temp.: between –10C and 80C (14F and 176F)
4) Start engine and drive vehicle under usual driving condition (described in DTC confirmation procedure of DTC
P0136) for 5 min. or longer and until engine is warmed up to normal operating temperature.
5) Keep vehicle speed at 30 – 40 mph, 50 – 60 km / h in 5th gear or “D” range for 5 min. or more.
6) Stop vehicle (do not turn ignition switch OFF).
7) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-67
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Is there DTC(s) other than fuel system
(DTC P0171 / P0172)?Go to applicable
DTC Diag. Flow
Table.Go to Step 3.
3Check HO2S-1 Output Voltage.
1) Connect scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and keep
it at 2000 r / min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator pedal
5 to 6 times continuously and take foot off from pedal to
enrich and enlean A / F mixture). See Fig. 1.
Does HO2S-1 output voltage deflect between below 0.3 V and
over 0.6 V repeatedly?Go to Step 4.Go to DTC
P0130 Diag.
Flow Table
(HO2S-1 circuit
check).
4Check Fuel Pressure (Refer to section 6E2 for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge.
3) Check fuel pressure. See Fig. 2.
With fuel pump operating
and engine at stop : 270 – 310 kPa, 2.7 – 3.1 kg / cm
2,
38.4 – 44.0 psi.
At specified idle speed : 200 – 240 kPa, 2.0 – 2.4 kg / cm
2,
28.4 – 34.1 psi.
Is measured value as specified?
Go to Step 5.Go to Diag. Flow
Table B-3 Fuel
Pressure Check.
5Check Fuel Injectors and Circuit.
1) Using sound scope (1) or such, check operating sound of
each injector (2) when engine is running. Cycle of operating
sound should vary according to engine speed. See Fig. 3.
If no sound or an unusual sound is heard, check injector
circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel injector
connector.
3) Check for proper connection to fuel injector at each terminal.
See Fig. 4.Go to Step 6.Check injector
circuit or replace
fuel injector(s).
4) If OK, then check injector resistance.
Injector Resistance: 12 – 13 ohm at 20C (68F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume referring to
Section 6E2. See Fig. 5.
Injected Fuel Volume: 38 – 48 cc / 15 sec 1.28 /
1.34 – 1.62 / 1.69 US / Imp.oz / 15 sec)
7) Check each injector for fuel leakage after injector closed.
Fuel Leakage: Less than 1 drop / min.
Is check result in step 1) and 3) to 7) satisfactory?
6Check EVAP Canister Purge Valve.
1) Disconnect purge hose (1) from EVAP canister.
2) Place finger against the end of disconnected hose.
3) Check that vacuum is not felt there when engine is cool and
running at idle. See Fig. 6.
Is vacuum felt?Check EVAP
control system
(See Section
6E2).Go to Step 7.
7Check intake manifold absolute pressure sensor for
performance (See DTC P0105 Diag. Flow Table).
Is it in good condition?Go to Step 8.Repair or
replace.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-79
1) 2) 3)4)
5) 6)7)
Engine speed
4000 r/min
0 Vehicle speed
0 50 – 55 mph
80 – 88 km/h
(Keep throttle
valve opening
constantly)
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 with 2 persons, a driver and a tester, on a level road.
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for:
–Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Intake air temp.: between –10C and 80C (14F and 158F)
2) Start engine and warm it up to normal operating temperature (70 – 11 0C, 158 – 230F) and run it at idle for
5 min.
3) Increase vehicle speed to 50 – 55 mph, 80 – 88 km / h in 5th gear or in “D” range.
4) Hold throttle valve at that opening position for 2 min. or longer.
5) Increase engine speed to 4000 r / min. in 3rd gear or in “2” range.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) till engine
speed reaches 1500 r / min.
7) Stop vehicle (don’t turn ignition switch OFF) and confirm test results according to following “Test Result Con-
firmation Flow Table.”
Test Result Confirmation Flow Table
STEPACTIONYESNO
1Check DTC in “DTC” mode and pending DTC in “ON
BOARD TEST”.
Is DTC or pending DTC displayed?Proceed to applicable
DTC flow table.Go to Step 2.
2Set scan tool to “READINESS TESTS” mode and
check if testing has been completed.
Is test completed?No DTC is detected.
(Confirmation test is
completed)Repeat DTC
confirmation
procedure.