2000 SUZUKI SWIFT throttle

6-40 ENGINE GENERAL INFORMATION AND DIAGNOSIS
For TYPE B (For applicable mode, refer to NOTE in “ECM VOLTAGE VALUES TABLE”) G02 17 Power source for back-up 10 – 14 V Anytime
TERMINAL NO. CIRCUIT NORMAL VOLT-
AGECONDITION
C421Ground––
2Ground––
3Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5–– –
6 Idle air control valve 0 – 13 V At specified idle speed after engine warmed up
7 Heater of HO2S-1 (if equipped) 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor 0 – 0.8 V and
4 – 6 VIgnition switch ON
12 Shield ground––
13 Heated oxygen sensor-1 (if equipped) Refer to DTC P0130 diag. flow table
CO adjusting resistor (if equipped)––
14 Engine coolant temp. sensor 0.55 - 0.95 V Ignition switch ON
Engine coolant temp. : 80°C (176°F)
15 Intake air temp. sensor 2.0 – 2.7 V Ignition switch ON
Intake air temp. : 20°C (68°F)
16 Throttle position sensor 0.2 – 1.0 V Ignition switch ON
Throttle valve at idle position
2.8 – 4.8 V Ignition switch ON
Throttle valve at full open position
17 EGR valve (stepper motor coil 3)
(if equipped)10 – 14 V Ignition switch ON
18 EGR valve (stepper motor coil 1)
(if equipped)10 – 14 V Ignition switch ON
19 Ignition coil #2––
20 Ignition coil #1––
21 Fuel injector NO.2 10 – 14 V Ignition switch ON
22 Power source for sensor 4.75 – 5.25 V Ignition switch ON
23 Crankshaft position sensor––
24–– –
25 knock sensor (if equipped) 2.1 – 2.9 V Ignition switch ON
26 Manifold absolute pressure sensor 3.3 – 4.0 V Ignition switch ON
Barometric pressure : 100 kPa (760 mmHg)
27–– –
28 EGR valve (stepper motor coil 4)
(if equipped)10 – 14 V Ignition switch ON
29 EGR valve (stepper motor coil 2)
(if equipped)10 – 14 V Ignition switch ON
30 A/C triple pressure switch 10 – 14 V A/C not operated
31 Fuel injector NO.3 10 – 14 V Ignition switch ON
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION

6-42 ENGINE GENERAL INFORMATION AND DIAGNOSIS
C4121 Stop lamp switch 0 V Ignition switch ON
Stop lamp switch OFF
10 – 14 V Ignition switch ON
Stop lamp switch ON
22 Vehicle speed sensor Indication
deflection
repeated
0 V and
10 – 14 VIgnition switch ON
Front left tire turned slowly with
front right tire locked
23–––
24––– TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
G021 A/C evaporator temp. sensor––
2 R-range signal (A/T) 0 V Ignition switch ON
3–––
4–––
5 Engine coolant temp. and barometric
pressure signal for TCM (A/T)Indication
deflection
repeated
0 V and
10 – 14 VIgnition switch ON
6 D-range ID-up signal (A/T) 10 – 14 V Ignition switch ON
7 Data link connector (SUZUKI serial
data line)4 – 6 V Ignition switch ON
8Blank––
9 Malfunction indicator lamp 0 – 1 V Ignition switch ON
10 – 14 V When engine running
10–––
11 Data link connector
(K line of ISO9141)10 – 14 V Ignition switch ON
12 Blank––
13 Electric load signal (–)0 – 2 V Ignition switch ON
Blower fan turned OFF
10 – 14 V Ignition switch ON
Blower fan turned ON
14 Sensor ground––
15 Throttle opening signal for TCM (A/T) Indication
deflection
repeated
0 V and
10 – 14 VIgnition switch ON
16 Tachometer (if equipped) 0 – 1 V Ignition switch ON
17–––

6-60 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0120 (DTC NO.13) THROTTLE POSITION CIRCUIT MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode no scan tool and check DTC.
[A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
DTC DETECTING CONDITION POSSIBLE CAUSE
Signal voltage high
or
Signal voltage low“ORN” circuit open
“GRY/BLU” circuit open or shorted to ground
“GRY/RED” circuit open or shorted to power or ground
TP sensor malfunction
ECM malfunction
C42-10
C42-22
5V5V
ECM
GRY/RED
GRY/BLU
ORN
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
C42-16 [B] C41-3 [A]
NOTE:
For TYPE A and TYOE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
When DTC P0105 (No.11), P0110 (No.18), P0115 (No.19) and P0120 (No.13) are indicated together, it
is possible that “ORN” or “GRY/RED” circuit is open.
When this DTC and P1700 are stored together, also clear DTC stored in TCM after completion of
repair.
When this DTC and DTC P0105 (No.11) are indicated together, it is possible that “GRY/RED” circuit
is open.

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-61
INSPECTION
Fig. 1 for Step 2Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check 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 throt-
tle valve from idle position to full open posi-
tion. 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.
3 Check Wire Harness.
1) Disconnect connector from TP sensor with
ignition switch OFF.
2) Check for proper connection to TP sensor at
“GRY/RED”, “GRY/BLU” and “ORN” wire
terminals.
3) If OK, then with ignition switch ON, check
voltage between each of “GRY/RED” or
“GRY/BLU” wire terminals and body
ground. See Fig. 2.
Is voltage about 4 – 6 V at each terminal?Go to Step 4.“GRY/RED” wire open,
“GRY/RED” wire shorted
to ground circuit or power
circuit or “GRY/BLU” wire,
“ORN” wire open or
shorted to ground circuit
or poor C42-22 or C41-3
(For TYPE A, See NOTE)
or C42-16 (For TYPE B,
See NOTE) connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
4 Check TP Sensor.
1) Check resistance between terminals of TP
sensor. See Fig. 3.
Between 1 and 2 : 2.5 – 6.0 kΩ
Between 1 and 3 : 100 Ω – 20 kΩ
varying according to throttle valve opening
Are measured values within specifications?“ORN” wire open or poor
C42-10 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.Replace TP sensor.

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-63
DTC P0121 THROTTLE POSITION CIRCUIT RANGE/PERFORMANCE PROB-
LEM
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
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. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
–Engine coolant temp. : 70 – 110°C, 158 – 230°F
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.
[A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
C42-10
C42-22
5V5V
ECM
GRY/RED
GRY/BLU
ORN
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
C42-16 [B]C41-3 [A]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC will set when the following conditions are detected.
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 (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 malfunction
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.

6-64 ENGINE GENERAL INFORMATION AND DIAGNOSIS
INSPECTION
Fig. 1 for Step 3Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Is SUZUKI scan tool available? Go to Step 3. Go to Step 4.
3 Check 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 sen-
sor output voltage when throttle valve is at
idle position and fully opened. See Fig. 1
and 3.
Dose voltage vary within specified value linearly
as shown in figure?If voltmeter was used,
check terminal C41-3 (For
TYPE A, See NOTE) or
C42-16 (For TYPE B, See
NOTE) for poor connec-
tion.
If OK, substitute a known-
good ECM and recheck.Go to Step 5.
4 Check TP Sensor and Its Circuit.
1) Turn ignition switch ON.
2) Check voltage at terminal C41-3 (For TYPE
A, See NOTE) or C42-16 (For TYPE B, See
NOTE) of ECM 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 C41-3 (For
TYPE A, See NOTE) or
C42-16 (For TYPE B, See
NOTE) for poor connec-
tion.
If OK, substitute a known-
good ECM and recheck.Go to Step 5.
5 Check 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 : 4.0 – 6.0 kΩ
Between 1 and 3 : 0.02 – 6.0 kΩ, varying
according to throttle valve opening.
Are measured values as specified?High resistance in “GRY/
RED”, “GRY/BLU” or
“ORN” circuit.
If wire and connection are
OK, substitute a known-
good ECM and recheck.Replace TP sensor.
[A] : When using SUZUKI scan tool:
[ A]

6-78 ENGINE GENERAL INFORMATION AND DIAGNOSIS
5 Check Fuel Injectors and Circuit.
1) Using sound scope (1) or such, check oper-
ating 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 cou-
pler) 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.
4) If OK, then check injector resistance.
Injector Resistance : 11.3 – 13.8 ohm at
20°C (68°F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume
(1) referring to Section 6E1. See Fig. 5.
Injected Fuel Volume : 43 – 47 cc/15 sec
1.45/1.51 – 1.58/1.65 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) satisfac-
tory?Go to Step 6. Check injector circuit or
replace fuel injector(s).
6 Check EVAP Canister Purge Valve.
1) Disconnect purge hose from EVAP canister
purge valve.
2) Place finger against the end of EVAP canis-
ter purge valve.
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 sys-
tem (See Section 6E1).Go to Step 7.
7 Check Intake manifold absolute pressure sen-
sor for performance (See DTC P0105 (No.11)
Diag. Flow Table).
Is it in good condition?Go to Step 8. Repair or replace.
8 Check Engine Coolant Temp. Sensor for perfor-
mance (See Section 6E1).
Is it in good condition?Go to Step 9. Replace engine coolant
temp. sensor.
9 Check Intake Air Temp. Sensor for perfor-
mance (See Section 6E1).
Is it in good condition?Go to Step 10. Replace intake air temp.
sensor.
10 Check 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.
11 Check PCV Valve for valve clogging (See Sec-
tion 6E1).
Is it good condition?Substitute a known-good
ECM and recheck.Replace PCV valve. Step Action Yes No

6-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC CONFIRMATION PROCEDURE
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)
–Ambient temp. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
–Engine coolant temp. : – 10 – 110°C, 14 – 230°F
4) Start engine and keep it at idle for 2 min. or more.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
6) If DTC is not detected at idle, consult usual driving based on information obtained in “Customer complaint
analysis” and “Freeze frame data check”.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
Engine under other than high revolution condition
Not on rough road
Engine speed changing rate (Below specified value)
Manifold absolute pressure changing rate (Below
specified value)
Throttle opening changing rate (Below specified
value)
Misfire rate per 200 or 1000 engine revolutions (how
much and how often crankshaft revolution speed
changes) is higher than specified valueEngine overheating
Vacuum leaks (air inhaling) from air intake system
Ignition system malfunction (spark plug(s), high-
tension cord(s), ignition coil assembly)
Fuel pressure out of specification
Fuel injector malfunction (clogged or leakage)
Engine compression out of specification
Valve lash (clearance) out of specification
Manifold absolute pressure sensor malfunction
Engine coolant temp. sensor malfunction
PCV valve malfunction
EVAP control system malfunction
EGR system malfunction
NOTE:
Among different types of random misfire, if misfire occurs at cylinders 1 and 4 or cylinders 3 and 2
simultaneously, it may not possible to reconfirm DTC by using the following DTC confirmation proce-
dure. When diagnosing the trouble of DTC P0300 (Random misfire detected) of the engine which is
apparently misfiring, even if DTC P0300 cannot be reconfirmed by using the following DTC confirma-
tion procedure, proceed to the following Diag. Flow Table.
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.
CAUTION:
For iridium spark plugs, do not adjust air gap or clean.
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE
DIAG. FLOW
TABLE”.