ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-13
MALFUNCTION INDICATOR LAMP (MIL)
CHECK
1) Turn ON ignition switch (but the engine at stop) and check that
MIL lights.
If MIL does not light up (or MIL dims), go to “Diagnostic Flow
Table A-1” for troubleshooting.
2) Start engine and check that MIL turns OFF.
If MIL remains ON and no DTC is stored in ECM (PCM), go to
“Diagnostic Flow Table A-2” for troubleshooting.
DIAGNOSTIC TROUBLE CODE (DTC) CHECK
1) Prepare SUZUKI scan tool (Tech-1) or generic scan tool.
2) With ignition switch OFF, connect it to data link connector (DLC)
(1) located on underside of instrument panel at driver’s seat side.
Special Tool:
(A): SUZUKI scan tool
(B): Mass storage cartridge
(C): 16 / 14 pin DLC cable
3) Turn ignition switch ON and confirm that MIL lights.
4) Read DTC, pending DTC and freeze frame data according to
instructions displayed on scan tool and print it or write it down.
Refer to scan tool operator’s manual for further details.
If communication between scan tool and ECM (PCM) is not pos-
sible, check if scan tool is communicable by connecting it to
ECM (PCM) in another vehicle. If communication is possible in
this case, scan tool is in good condition. Then check data link
connector and serial data line (circuit) in the vehicle with which
communication was not possible.
5) After completing the check, turn ignition switch off and discon-
nect scan tool from data link connector.
6-30 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
SCAN TOOL DATACONDITIONNORMAL CONDITION /
REFERENCE VALUES
DESIRED IDLEAt idling with no load after warming up, M / T850 r / min(DESIRED IDLE SPEED)
gg,
at neutral, A / T at “P” range850 r / min
TP SENSOR VOLT
(THROTTLE POSITIONIgnition switch
ON / engine
Throttle valve fully closedMore than 0.2 V(
SENSOR OUTPUT
VOLTAGE)ON / engine
stoppedThrottle valve fully openLess than 4.8 V
INJ PULSE WIDTH
(FUEL INJECTIONAt specified idle speed with no load after
warming up0.8 – 2.3 msec.(
PULSE WIDTH)At 2500 r / min with no load after warming up0.8 – 2.3 msec.
IAC FLOW DUTY (IDLE
AIR CONTROL FLOW
DUTY)
At idling with no load after warming up20 – 40%
TOTAL FUEL TRIMAt specified idle speed after warming up–35 – +35%
BATTERY VOLTAGEIgnition switch ON / engine stop10 – 14 V
CANIST PRG DUTY
(EVAP CANISTER
PURGE FLOW DUTY)
At specified idle speed after warming up0 – 100%
CLOSED THROT POS
(CLOSED THROTTLEThrottle valve at idle positionON(CLOSED THROTTLE
POSITION)Throttle valve opens larger than idle positionOFF
FUEL CUTWhen engine is at fuel cut conditionONFUEL CUTOther than fuel cut conditionOFF
RAD FAN
(RADIATOR FANIgnition switch
ON
Engine coolant temp.:
Lower than 92.5C
(199F)
OFF
(
CONTROL RELAY)ONEngine coolant temp.:
97.5C (208F) or higherON
ELECTRIC LOAD
Ignition switch ON / Headlight, small light,
heater fan and rear window defogger all
turned OFF
OFF
ELECTRIC LOADIgnition switch ON / Headlight, small light,
heater fan or rear window defogger turned
ON
ON
A / C SWITCH
Engine running after warming up, A / C not
operatingOFF
A/C SWITCHEngine running after warming up, A / C
operatingON
PSP SWITCH
Engine running at idle speed and steering wheel
at straight-ahead position.OFF
(if equipped).Engine running at idle speed and steering wheel
turned to the right or left as far as it stops.ON
FUEL TANK LEVEL––––––––––––0 – 100%
BAROMETRIC PRESS––––––––––––Display the barometric pressure
FUEL PUMP
Within 3 seconds after ignition switch ON or
engine runningON
Engine stop at ignition switch ON.OFF
6-32 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
SCAN TOOL DATA DEFINITIONS
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air / fuel ratio feedback loop status displayed as either
open or closed loop. Open indicates that ECM (PCM)
ignores feedback from the exhaust oxygen sensor.
Closed indicates final injection duration is corrected
for oxygen sensor feedback.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum
possible load. Value is calculated mathematically us-
ing the formula: actual (current) intake air volume
maximum possible intake air volume x 100%.
COOLANT TEMP.
(ENGINE COOLANT TEMPERATURE, C, F)
It is detected by engine coolant temp. sensor
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim value represents short term
corrections to the air / fuel mixture computation. A val-
ue of 0 indicates no correction, a value greater than
0 means an enrichment correction, and a value less
than 0 implies an enleanment correction.
LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim Value represents long term correc-
tions to the air / fuel mixture computation. A value of 0
indicates no correction, a value greater than 0 means
an enrichment correction, and a value less than 0 im-
plies an enleanment correction.
MAP (INTAKE MANIFOLD ABSOLUTE
PRESSURE, kPa, inHg)
It is detected by manifold absolute pressure sensor and
used (among other things) to compute engine load.
ENGINE SPEED (rpm)
It is computed by reference pulses from crankshaft
position sensor.
VEHICLE SPEED (km / h, MPH)
It is computed based on pulse signals from vehicle
speed sensor.
IGNITION ADVANCE
(IGNITION TIMING ADVANCE FOR NO.1
CYLINDER, )
Ignition timing of NO.1 cylinder is commanded by
ECM (PCM). The actual ignition timing should be
checked by using the timing light.
INTAKE AIR TEMP. (C, F)
It is detected by intake air temp. sensor and used to
determine the amount of air passing into the intake
manifold as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm / s, lb / min)
It represents total mass of air entering intake manifold
which is computed based on signals from MAP sen-
sor, IAT sensor, TP sensor, etc.
THROTTLE POS
(ABSOLUTE THROTTLE POSITION, %)
When throttle position sensor is fully closed position,
throttle opening is indicated as 0% and 100% full open
position.
OXYGEN SENSOR B1 S1
(HEATED OXYGEN SENSOR-1, V)
It indicates output voltage of HO2S-1 installed on ex-
haust manifold (pre-catalyst).
OXYGEN SENSOR B1 S2
(HEATED OXYGEN SENSOR-2, V)
It indicates output voltage of HO2S-2 installed on ex-
haust pipe (post-catalyst). It is used to detect catalyst
deterioration.
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM (PCM) internal pa-
rameter which indicates the ECM (PCM) requested
idle. If the engine is not running, this number is not valid.
TP SENSOR VOLT (THROTTLE POSITION
SENSOR OUTPUT VOLTAGE, V)
The Throttle Position Sensor reading provides throttle
valve opening information in the form of voltage.
INJ PULSE WIDTH
(FUEL INJECTION PULSE WIDTH, msec.)
This parameter indicates time of the injector drive
(valve opening) pulse which is output from ECM
(PCM) (but injector drive time of NO.1 cylinder for
multiport fuel injection).
IAC FLOW DUTY (IDLE AIR (SPEED) CONTROL
DUTY, %)
This parameter indicates opening of the throttle valve
in terms of percentage to opening controllable by the
ISC actuator.
TOTAL FUEL TRIM (%)
The value of Total Fuel Trim is obtained by putting val-
ues of short Term Fuel Trim and Long Term Fuel Trim
together. This value indicates how much correction is
necessary to keep the air / fuel mixture stoichiomet-
rical.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage in-
putted from main relay to ECM (PCM).
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-33
CANIST PURGE DUTY (EVAP CANISTER
PURGE FLOW DUTY, %)
This parameter indicates valve ON (valve open) time
rate within a certain set cycle of EVAP purge solenoid
valve which controls the amount of EVAP purge.
0% means that the purge valve is completely closed
while 100% is a fully open valve.
CLOSED THROTTLE POSITION (ON / OFF)
This parameter will read ON when throttle valve is ful-
ly closed, or OFF when the throttle is not fully closed.
FUEL CUT (ON / OFF)
ON : Fuel being cut (output signal to injector is
stopped)
OFF : Fuel not being cut
RAD FAN
(RADIATOR FAN CONTROL RELAY, ON / OFF)
ON : Command for radiator fan control relay opera-
tion being output.
OFF : Command for relay operation not being out-
put.
ELECTRIC LOAD (ON / OFF)
ON : Headlight, small light, heater fan or rear win-
dow defogger ON signal inputted.
OFF : Above electric loads all turned OFF.
A / C SWITCH (ON / OFF)
ON : Command for A / C operation being output
from ECM (PCM) to A / C amplifier.
OFF : Command for A / C operation not being output.
FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in the
fuel tank. As the detectable range of the fuel level sen-
sor is set as 0 to 100%, however, with some models
whose fuel tank capacity is smaller, the indicated fuel
level may be only 70% even when the fuel tank is full.
PSP SWITCH (ON / OFF)
ON : PSP switch detects P / S operation (high PS
pressure).
OFF : PSP switch not detects P / S operation.
BAROMETRIC PRESS (kPa, inHg)
This parameter represents a measurement of baro-
metric air pressure and is used for altitude correction
of the fuel injection quantity and ISC actuator control.
FUEL PUMP (ON / OFF)
ON is displayed when the ECM (or PCM) activates the
fuel pump via the fuel pump relay switch.
VSS (A / T) (km / h, MPH)
If is computed by using pulse signals from vehicle
(output) speed sensor on automatic transmission.
TRANS RANGE (TRANSMISSION RANGE
SENSOR, P, R, N, D, 2 OR L)
It is indicated transmission range detected by trans-
mission range sensor.
SHIFT SOL 1-CON (SHIFT SOLENOID-1,
ON / OFF)
ON : ON command being output to shift solenoid-1
OFF : ON command not being output.
SHIFT SOL 2-CON (SHIFT SOLENOID-2,
ON / OFF)
ON : ON command being output to shift solenoid-2
OFF : ON command not being output.
SHIFT SOL 1-MON (SHIFT SOLENOID-1,
ON / OFF)
The monitor result of the shift solenoid-1 circuit is dis-
played.
ON : Electricity being passed to shift solenoid-1 or
circuit open.
OFF : Electricity not being passed or circuit short.
SHIFT SOL 2-MON (SHIFT SOLENOID-2,
ON / OFF)
The monitor result of the shift solenoid-2 circuit is dis-
played.
ON : Electricity being passed to shift solenoid-2 or
circuit open.
OFF : Electricity not being passed or circuit short.
THROT POS LEVEL (THROTTLE POSITION
LEVEL FOR A / T, “0”, “1”, “2”, “3”, “4”, “5”, “6”
or “7”)
This parameter indicates which level (zone) the
throttle valve opening is in. The throttle opening is di-
vided into 8 levels (zones) from “0” (about idle posi-
tion) to “7” (about full open) and signals are assigned
to each opening level (zone). ECM (PCM) control the
automatic gear change of the automatic transmission
by using these signals according to the signal from
the TP sensor.
GEAR POSITION
This parameter indicates the A / T gear position which
is computed on signals from the Transmission Range
Switch, VSS, TP Sensor, and so forth.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-47
Fig. 1 for Step 2 Fig. 2 for Step 3 Fig. 3 for Step 4
Scan tool
DLC
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check IAT Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition switch
OFF.
2) Turn ignition switch ON.
3) Check intake air temp. displayed on scan tool.
See Fig. 1.
Is –40C (–40F) or 119C (246F) indicated?Go to Step 3.Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.
3Check Wire Harness.
1) Disconnect IAT sensor connector with ignition
switch OFF.
2) Check for proper connection to IAT sensor at
“Gr” and “G” wire terminals.
3) If OK, then with ignition switch ON, is voltage
applied to “Gr” wire terminal about 4 – 6 V? See
Fig. 2.Go to Step 5.“Gr” wire open or
shorted to power, or
poor C01-14
connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.
4Does scan tool indicate –40C (–40F) at Step 2.Go to Step 6.Go to Step 5.
5Check Wire Harness.
1) Check intake air temp. displayed on scan tool
with ignition switch ON.
Is –40C (–40F) indicated?Replace IAT sensor.“Gr” wire shorted to
ground.
If wire is OK, substitute
a known-good ECM
(PCM) and recheck.
6Check Wire Harness.
1) Using service wire, connect IAT sensor
connector terminals.
2) Check intake air temp. displayed on scan tool
with ignition switch ON. See Fig. 3.
Is 119C (246F) indicated?Replace IAT sensor.“Gr” wire open or poor
C01-9 connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-49
Fig. 1 for Step 2 Fig. 2 for Step 3 Fig. 3 for Step 4
Scan tool
DLC
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check ECT Sensor and Its Circuit.
1) Connect scan tool with ignition switch OFF.
2) Turn ignition switch ON.
3) Check engine coolant temp. displayed on scan
tool. See Fig. 1.
Is –40C (–40F) or 119C (246F) indicated?Go to Step 3.Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0 A.
3Check Wire Harness.
1) Disconnect ECT sensor connector.
2) Check engine coolant temp. displayed on scan
tool.
Is –40C (–40F) indicated?Replace ECT sensor.“Gr / W” wire shorted to
ground.
If wire is OK, substitute
a known-good ECM
(PCM) and recheck.
4Does scan tool indicate –40C (–40F) at Step 2.Go to Step 6.Go to Step 5.
5Check Wire Harness.
1) Disconnect ECT sensor connector with
ignition switch OFF.
2) Check for proper connection to ECT sensor at
“G” and “Gr / W” wire terminals.
3) If OK, then with ignition switch ON, is voltage
applied to “G” wire terminal about 4 – 6 V?
See Fig. 2.Go to Step 4.“Gr / W” wire open or
shorted to power, or
poor C01-7 connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.
6Check Wire Harness.
1) Using service wire, connect ECT sensor
connector terminals. See Fig. 3.
2) Turn ignition switch ON and check engine
coolant temp. displayed on scan tool.
Is 119C (246F) indicated?Replace ECT sensor.“G” wire open or
poor C01-9 connection.
If wire and connection
are OK, substitute a
known-good ECM
(PCM) and recheck.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-51
Fig. 1 for Step 2 Fig. 2 for Step 3 Fig. 3 for Step 4
Scan tool
“Lg” “Lg/W”
“3”“4”
“1”
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE”
performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check TP Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF and then turn ignition switch
ON.
2) Check throttle valve opening percentage
displayed on scan tool. See Fig. 1.
Is it displayed 2% or less?
3) Check throttle valve opening percentage
displayed on scan tool while opening
throttle valve from idle position to full open
position. See Fig. 1.
Is it displayed 96% or higher?Go to Step 3.Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0 A.
3Check Wire Harness.
1) Disconnect connector from TP sensor
with ignition switch OFF.
2) Check for proper connection to TP sensor
at “Lg”, “Lg/W” and “G” wire terminal.
3) If OK, then with ignition switch ON, check
voltage at each of “Lg” and “Lg / W” wire
terminals. See Fig. 2.
Is voltage about 4 – 6 V at each terminal?Go to Step 4.“Lg” wire open, “Lg”
wire shorted to ground
circuit or power circuit or
“G” wire, “Lg / W” wire
open or shorted to ground
circuit or poor C01-1 or
C01-6 connection.
If wire and connection are
OK, substitute a known-
good ECM (PCM) and
recheck.
4Check TP Sensor.
1) Check resistance between terminals of
TP sensor. See Fig. 3.
Between 1 and 4: 2.87 – 5.33 kΩ
Between 1 and 3: 100 Ω – 20 kΩ, varying
according to throttle valve opening.
Are measured values within specifications?“G” wire open or poor
C01–9 connection.
If wire and connection are
OK, substitute a known-
good ECM (PCM) and
recheck.Replace TP sensor.
6-60 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
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)
–Ambient temp.: –10C, 14F or higher
–Intake air temp.: 70C, 158F or lower
–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.