Page 209 of 557

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-53
Fig. 1 for Step 2 Fig. 2 for Step 2 Fig. 3 for Step 2
Fig. 4 for Step 3
Closed
(condition “A”)Fully open
Throttle Opening When using SUZUKI scan tool:
When not using SUZUKI scan tool:
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Check TP Sensor and Its Circuit.
When using SUZUKI scan tool:
1) Turn ignition switch OFF and connect SUZUKI scan tool to
DLC.
2) Turn ignition switch ON and check TP sensor output
voltage when throttle valve is at idle position and fully
opened. See Fig. 1 and 3.
When not using SUZUKI scan tool:
1) Turn ignition switch ON.
2) Check voltage at terminal C03-5 of ECM (PCM) connector
connected, when throttle valve is at idle position and fully
opened. See Fig. 2 and 3.
Dose voltage vary within specified value linearly as shown in
figure?If voltmeter was
used, check
terminal C03-5 for
poor connection.
If OK, substitute a
known-good ECM
(PCM) and
recheck.Go to Step 3.
3Check TP Sensor.
1) Turn ignition switch OFF.
2) Disconnect TP sensor connector.
3) Check for proper connection to TP sensor at each terminal.
4) If OK, then measure resistance between terminals and
check if each measured value is as specified below.
See Fig. 4.
Between 1 and 2: 2.5 – 6.0 kΩ
Between 1 and 3: 170 Ω – 15.5 kΩ, varying according to
throttle valve opening.
Are measured values as specified?High resistance in
“P”, “Gr” or “G”
circuit.
If wire and
connection are
OK, substitute a
known-good ECM
(PCM) and
recheck.Replace TP
sensor.
Page 210 of 557

6-1-54 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Ignition
switch
Main
fuse
To HO2S-2 heaterTo other sensor
Heater Fuse box
DTC P0130 HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-1)
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
When running at idle speed after engine warmed up
and running at specified vehicle speed, HO2S-1
output voltage does not go 0.3 V below or over
0.6 V.
2 driving cycle detection logic, Monitoring once / 1
driving.Heated oxygen sensor-1 malfunction
“G” or “R” circuit open (poor connection) or short
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.
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 176F)
2) Warm up engine to normal operating temperature.
3) Drive vehicle at 38 – 50 mph, 60 – 80 km / h for 2 min.
4) Stop vehicle and run engine at idle for 2 min.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
Page 212 of 557
6-1-56 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1
HO2S-1
Output
voltage1 cycle time
Response time
DTC P0133 HEATED OXYGEN SENSOR (HO2S) CIRCUIT SLOW RESPONSE
(SENSOR-1)
WIRING DIAGRAM / CIRCUIT DESCRIPTION – Refer to DTC P0130 section.
DTC DETECTING CONDITION
POSSIBLE CAUSE
When running at specified idle speed after engine
warmed up and running at specified vehicle speed,
response time (time to change from lean to rich or
from rich to lean) of HO2S-1 output voltage is about
1 sec. at minimum or average time of 1 cycle is 5 sec.
at minimum. See. Fig. 1
2 driving cycle detection logic, Monitoring once / 1
driving.Heated oxygen sensor-1 malfunction
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 HO2S-1 (DTC P0133)?Go to applicable DTC
Diag. Flow Table.Replace HO2S-1.
Page 213 of 557

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.
Page 214 of 557

Ignition
switch
Main
fuse
To HO2S-2 heaterTo other sensor
Heater Fuse box
6-1-58 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
DTC P0135 HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT
MALFUNCTION (SENSOR-1)
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC will set when A or B condition is met.
A:
Low voltage at terminal C01-7 when engine is
running at high load.
B:
High voltage at terminal C01-7 when engine is
running under condition other than above.
2 driving cycle detection logic, Continuous
monitoring.HO2S-1 heater circuit open or shorted to ground
ECM (PCM) malfunction
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.
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON, start engine and keep it at idle for 1 min.
3) Start vehicle and depress accelerator pedal fully for 5 sec. or longer.
4) Stop vehicle.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
Page 215 of 557

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.
Page 216 of 557
6-1-60 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
To other sensor
Main
fuseIgnition
switch
Heater
To HO2S-1
heater
DTC P0136 HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-2)
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC will set when A or B condition is detected.
A. Max. output voltage of HO2S-2 is lower than specified value or
Min. output voltage is higher than specified value while vehicle
driving.
B. Engine is warmed up and HO2S-2 voltage is 4.5 V or more.
(circuit open)
2 driving cycle detection logic, monitoring once / 1 driving.Exhaust gas leakage
“G” or “R” circuit open or short
Heated oxygen sensor-2 malfunction
Fuel system malfunction
Page 217 of 557

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.