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.
Ignition coil
Igniter
Ignition switch
Main
fuse
Injector resistor
Fuel injector
Crankshaft
position sensor
Camshaft
position sensor
Ground
at engine “I / G COIL METER”
Main relay
6-68 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0300 RANDOM MISFIRE DETECTED (Misfire detected at 2 or more
cylinders)
DTC P0301 CYLINDER 1 MISFIRE DETECTED
DTC P0302 CYLINDER 2 MISFIRE DETECTED
DTC P0303 CYLINDER 3 MISFIRE DETECTED
CIRCUIT DESCRIPTION
ECM (PCM) monitors crankshaft revolution speed and engine speed via the crankshaft position sensor and cylin-
der No. via the camshaft position sensor. Then it calculates the change in the crankshaft revolution speed and from
how many times such change occurred in every 200 or 1000 engine revolutions, it detects occurrence of misfire.
When ECM (PCM) detects a misfire (misfire rate per 200 revolutions) which can cause overheat and damage to
the three way catalytic converter, it makes the malfunction indicator lamp (MIL) flash as long as misfire occurs at
that rate.
After that, however, when the misfire rate drops, MIL remains ON until it has been judged as normal 3 times under
the same driving conditions.
Also, when ECM (PCM) detects a misfire (misfire rate per 1000 revolutions) which will not cause damage to three
way catalytic converter but can cause exhaust emission to be deteriorated, it makes MIL light according to the 2
driving cycle detection logic.
Oscilloscope Waveforms
Crankshaft
timing belt pulleyCKP
sensor
2V/Div.
5ms/Div.
Waveforms at specified idle speed
6-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0335 CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
No CKP sensor signal during 1 revolution of
camshaft.CKP sensor circuit open or short.
Crankshaft timing belt pulley teeth damaged.
CKP sensor malfunction, foreign material being
attached or improper installation.
ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-3 (+) and C01-11 (–) of ECM (PCM) connector connected to ECM
(PCM) and check CKP sensor signal.
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.
Display of fuel injection signal using oscilloscope
1. CMP sensor signal
2. Fuel injector signal
3. Fuel injection time
2V/Div.
20V/Div.1
2
10ms/Div
Waveforms at specified idle speed 3 Sensor rotor
in distributorCamshaft
position sensor
6-74 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0340 CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
No CMP sensor signal for 2 seconds at engine
cranking (CKP sensor signal is inputted).CMP sensor circuit open or short.
Signal rotor teeth damaged.
CMP sensor malfunction, foreign material being
attached or improper installation.
ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-2 and C01-10 of ECM (PCM) connector connected to ECM (PCM)
and check CMP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC.
2) Start engine and keep it at idle for 1 min.
3) Select “DTC” mode on scan tool and check DTC.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-75
Fig. 1 for Step 3 Fig. 2 for Step 5
“a”: Air gap
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Is DTC P1500 (Engine starter signal circuit
malfunction) detected?Go to DTC P1500
Diag. Flow Table.Go to Step 3.
3Check CMP Sensor for Resistance.
1) Measure resistance of CMP sensor by referring to
“CMP SENSOR (PICK UP COIL) RESISTANCE”
in SECTION 6F.
Is resistance within specified value?Go to Step 4.Faulty CMP sensor.
4Check Wire Harness.
1) With ignition switch at OFF position, disconnect
ECM (PCM) electrical connectors.
2) Measure resistance from terminal “C01-2” to
“C01-10” of ECM (PCM) connector. See Fig. 1.
Is resistance within 185 – 275 Ω at 20C (68F)?Go to Step 5.“W” or “Or” wire open
or short.
Poor connection of
CMP sensor
connector terminal.
5Check Air Gap Between Rotor Tooth and Sensor. See
Fig. 2.
1) Remove Distributor cap.
2) Visually inspect CMP sensor signal rotor for
damage.
3) Measure air gap by referring “SIGNAL ROTOR
AIR GAP” in Section 6F.
Was any damage found?Faulty CMP sensor
signal rotor.Poor connection of
ECM (PCM)
connector terminal.
If OK, substitute a
known-good ECM
(PCM) and recheck
CMP.
Main
fuseMain relay
Idle speed
control relay
To TP sensor
Idle speed control actuator
6-86 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0505 IDLE CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC will set when A, B or C condition is met.
A: Throttle opening change is small as compared with
electrically live time.
B: Throttle valve opening is not within its target range
with CTP switch ON.
C: Drive voltage exists though ECM (PCM) is not
outputting ISC drive command.Malajusted accelerater cable
Poor movement of throttle valve
Closed throttle position switch malfunction
Idle speed control actuator malfunction
Idle speed control relay malfunction
“Gr / B”, “Gr / Y”, “Gr”, “Gr / R”, “Gr / G”, “Lg” or “B/Bl”
circuit open or short
Throttle position sensor malfunction
ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start cold engine.
4) Run it idle for 5 min.
5) Select “DTC” mode on scan tool and check DTC.
NOTE:
If engine speed changes up and down when engine speed is increased by opening throttle valve more
than half but not changing its opening, it is possible that closed throttle position switch is malfunction-
ing.
6-1
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-1
GENERAL INFORMATION6-1- 3 . . . . . . . . . . . . . .
ENGINE DIAGNOSIS6-1- 6 . . . . . . . . . . . . . . . . . . .
General Description 6-1- 6. . . . . . . . . . . . . . . . . . .
On-Board Diagnostic System 6-1- 6. . . . . . . . . .
Precaution in Diagnosing Trouble 6-1- 9. . . . . . .
Engine Diagnostic Flow Table 6-1-10. . . . . . . . . .
Customer Problem Inspection From 6-1-12. . .
Malfunction Indicator Lamp Check 6-1-13. . . .
Diagnostic Trouble Code Check 6-1-13. . . . . .
Diagnostic Trouble Code Clearance 6-1-14. . .
Diagnostic Trouble Code Table 6-1-15. . . . . . .
Fail-safe Table 6-1-18. . . . . . . . . . . . . . . . . . . . .
Visual Inspection 6-1-19. . . . . . . . . . . . . . . . . . .
Engine Basic Inspection 6-1-20. . . . . . . . . . . . .
Engine Diagnosis Table 6-1-22. . . . . . . . . . . . .
Scan Tool Data 6-1-29. . . . . . . . . . . . . . . . . . . . . . .
Inspection of ECM (PCM) and Its
Circuits 6-1-33. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage Check 6-1-33. . . . . . . . . . . . . . . . . . . . .
Resistance Check 6-1-37. . . . . . . . . . . . . . . . . .
Component Location 6-1-38. . . . . . . . . . . . . . . . . .
Table A-1 MIL Circuit Check
(Lamp does not come on) 6-1-39. . . . . . . . . . . . Table A-2 MIL Circuit Check
(Lamp remains ON) 6-1-40. . . . . . . . . . . . . . . . . .
Table A-3 ECM (PCM) Power and
Ground Circuit Check 6-1-41. . . . . . . . . . . . . . . .
DTC P0105 MAP Circuit Malfunction 6-1-43. . . .
DTC P0110 IAT Circuit Malfunction 6-1-46. . . . .
DTC P0115 ECT Circuit Malfunction 6-1-48. . . .
DTC P0120 Throttle Position Circuit
Malfunction 6-1-50. . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0121 Throttle Position Circuit
Range / Performance Problem 6-1-52. . . . . . . . .
DTC P0130 HO2S Circuit Malfunction
(Sensor-1) 6-1-54. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0133 HO2S Circuit Slow
Response (Sensor-1) 6-1-56. . . . . . . . . . . . . . . .
DTC P0134 HO2S Circuit No Activity
Detected 6-1-57. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0135 HO2S Heater Circuit
Malfunction (Sensor-1) 6-1-58. . . . . . . . . . . . . . .
DTC P0136 HO2S Circuit Malfunction
(Sensor-2) 6-1-60. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0141 HO2S Heater Circuit
Malfunction (Sensor-2) 6-1-63. . . . . . . . . . . . . . .
DTC P0171 Fuel System Too Lean 6-1-65. . . . .
DTC P0172 Fuel System Too Rich 6-1-65. . . . . .
SECTION 6-1
ENGINE GENERAL INFORMATION
AND DIAGNOSIS
(SFI FOR G13)
WARNING:
For vehicles equipped with Supplemental Restraint (Air Bag) System:
Service on and around the air bag system components or wiring must be performed only by an autho-
rized SUZUKI dealer. Refer to “Air Bag System Components and Wiring Location View” under “Gener-
al Description” in air bag system section in order to confirm whether you are performing service on
or near the air bag system components or wiring. Please observe all WARNINGS and “Service Precau-
tions” under “On-Vehicle Service” in air bag system section before performing service on or around
the air bag system components or wiring. Failure to follow WARNINGS could result in unintentional
activation of the system or could render the system inoperative. Either of these two conditions may
result in severe injury.
Technical service work must be started at least 90 seconds after the ignition switch is turned to the
“LOCK” position and the negative cable is disconnected from the battery. Otherwise, the system may
be activated by reserve energy in the Sensing and Diagnostic Module (SDM).
CONTENTS