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.
6-36 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
CONNECTOR “C01”
TER-
MINALWIRE
COLORCIRCUITSTANDARD
VOLTAGECONDITION
1LgPower source for sensor4.75 – 5.25 VIgnition switch ON
2OrCamshaft position sensor (+)——
3W/BCrankshaft position sensor
(+)——
4Gr / GClosed throttle position switch
0 – 1 V
Ignition switch ON, ISC actuator
plunger is in contact with throttle lever
screw
4Gr / G(In ISC actuator)
4 – 6 V
Ignition switch ON
Plunger is apart from throttle lever
screw
5Lg / RManifold absolute pressure
sensor3.3 – 4.0 V
Ignition switch ON
Barometric pressure: 100 kPa,
760 mmHg
6Lg / WThrottle position sensor
0.2 – 1.0 V
Ignition switch ON, when clearance
between throttle lever and throttle stop
screw is less than 0.35 mm (0.014 in.)
2.8 – 4.8 VIgnition switch ON
Throttle valve at full open position
7Gr / WEngine coolant temp. sensor0.55 – 0.95 VIgnition switch ON
Engine coolant temp.: 80C (176F)
8P/BHeater of H02S-110 – 14 VIgnition switch ON
9GGround for sensors——
10WCamshaft position sensor (–)——
11W/RCrankshaft position sensor
(+)——
12W/BEFE heater monitor0 – 1 VHeater relay OFF12W/BEFE heater monitor10 – 14 VHeater relay ON
13RHeated oxygen sensor-1Refer to DTC flow chart
14GrIntake air temp. sensor2.0 – 2.7 V
Ignition switch ON
Sensor ambient temp.
(Intake air temp): 20C (68F)
10 – 14 VIgnition switch ON
15Bl / WPower steering pressure
switch (If equipped)
0 – 1 V
With engine running at idle speed,
turning steering wheel to the right or left
as far as it stops, repeating it a few
times
16B/YEngine start switch6 – 12 VWhile engine cranking16B/Yg
(Engine start signal)0 – 1 VOther than above
To other sensors Throttle
position
sensorTo other sensors
6-50 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0120 THROTTLE POSITION CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Signal voltage high
or
Signal voltage low“G” circuit open
“Lg / W” circuit open or shorted to ground
“Lg” circuit open or shorted to power or ground
TP sensor malfunction
ECM (PCM) malfunction
NOTE:
When DTC P0105, P0110, P0115 and / or P0120 are indicated together, it is possible that “G” circuit is
open.
When DTC P0105, P0120 and / or P0510 are indicated together it is possible that “Lg” circuit is open.
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
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.
To other sensors Throttle
position
sensorTo other sensors
6-52 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0121 THROTTLE POSITION CIRCUIT RANGE / PERFORMANCE
PROBLEM
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
After engine warmed up.
While vehicle running at specified engine speed.
No change in intake manifold pressure (constant throttle opening)
Difference between actual throttle opening (detected from TP sensor)
and opening calculated by ECM (PCM) (Obtained on the basis of
engine speed and intake manifold pressure) in larger than specified
value.
2 driving cycle detection logic, continuous monitoringTP sensor malfunction
High resistance in the circuit
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, 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
–Engine coolant temp.: 70 – 11 0C, 158 – 230F
2) Warm up engine to normal operating temperature.
3) Increase vehicle speed to 30 – 40 mph, 50 – 60 km / h in 3rd gear or “D” range and hold throttle valve at that
opening position for 1 min.
4) Stop vehicle.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-53
Fig. 1 for Step 2 Fig. 2 for Step 2
Fig. 3 for Step 3
Closed
(condition “A”)Fully open
Throttle Opening
Condition “A”
Clearance between throttle lever and
throttle stop screw is less than 0.35 mm
(0.014 in.).
clearance
“1”“3”“4”
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) 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 2.
Dose voltage vary within specified value linearly as shown in
figure?If voltmeter was
used, check
terminal C01-6 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. 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 as specified?High resistance in
“Lg”, “Lg / W” or
“G” circuit.
If wire and
connection are
OK, substitute a
known-good ECM
(PCM) and
recheck.Replace TP
sensor.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-67
Fig. 1 for Step 3 Fig. 2 for Step 4 Fig. 3 for Step 5
Fig. 4 for Step 6
1. Throttle body
2. Fuel feed hose
GoodNo good
STEPACTIONYESNO
8Check engine coolant temp. sensor for performance
(See Section 6E1).
Is it in good condition?Go to Step 9.Replace engine
coolant temp. sensor.
9Check intake air temp. sensor for performance
(See Section 6E1).
Is it in good condition?Go to Step 10.Replace intake air
temp. sensor.
10Check throttle position sensor for performance (See
Step 4 of DTC P0121 Diag. Flow Table).
Is it in good condition?Go to Step 11.Replace throttle
position sensor.
11Check PCV valve for valve clogging (See Section
6E1).
Is it good condition?Substitute a known-
good ECM (PCM) and
recheck.Replace PCV valve.