Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-73
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.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine
Diag. Flow Table”.
2 Is there DTC other than Fuel system (DTC P0171/
P0172) and misfire (DTC P0300 – P0304)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-79
DTC P0335 (DTC No.23) Crankshaft Position (CKP) Sensor Circuit Malfunction
CIRCUIT DESCRIPTION
REFERENCE
Connect oscilloscope between terminals E19-23 of ECM connector connected to ECM and body ground and
check CKP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC and crank engine for 2 sec.
2) Select “DTC” mode on scan tool and check DTC.
DTC DETECTING CONDITION POSSIBLE CAUSE
NO CKP sensor signal for 2 seconds at engine crank-
ing.CKP sensor circuit open or short.
Signal teeth damaged.
CKP sensor malfunction, foreign material being
attached or improper installation.
ECM malfunction.
1. 10° signal [A] : Oscilloscope Waveforms [C] : Waveforms at 2000 rpm
2. 30° signal [B] : Waveforms at idle speed
Downloaded from www.Manualslib.com manuals search engine 6-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0340 (DTC No.15) Camshaft Position (CMP) Sensor Circuit Malfunction
CIRCUIT DESCRIPTION
REFERENCE
Connect oscilloscope between terminals E19-11 of ECM connector connected to ECM and body ground 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.
DTC DETECTING CONDITION POSSIBLE CAUSE
The number of CMP sensor signal pulses is incor-
rect during 8 revolution of crankshaft.CMP sensor circuit open or short.
Signal rotor teeth damaged.
CMP sensor malfunction, foreign material being
attached or improper installation.
ECM malfunction.
CMP sensor phase lag.
1. No.1 cylinder 3. No.3 cylinder [A] : Oscilloscope Waveforms [C] : CKP sensor waveform
2. No.2 cylinder 4. No.4 cylinder [B] : Waveforms at specified idle speed [D] : CMP sensor waveform
Downloaded from www.Manualslib.com manuals search engine 6-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0500 (DTC No.16) Vehicle Speed Sensor (VSS) Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC and warm up engine to normal operating temperature.
2) Increase vehicle speed to 50 mph, 80 km/h in 3rd gear or “2” range while observing vehicle speed displayed
on scan tool.
3) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for 4
sec. or more.
4) Check pending DTC and DTC.
1. VSS 3. VSS connector [B] : Case of TYPE B is shown (See NOTE)
2. Combination meter [A] : Case of TYPE A is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
DTC DETECTING CONDITION POSSIBLE CAUSE
VSS signal not inputted while vehicle running in “D”
range or during fuel cut at deceleration.
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring“B/Or” circuit open
“Y” or “Bl/B” circuit open or short
VSS malfunction
ECM malfunction
Speedometer 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.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-95
INSPECTION
[A] Fig. 1 for Step 5 / [B] Fig. 2 for Step 4 and Step 6Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Does speedometer indicate vehicle speed? Go to Step 3. Go to Step 5.
3 Check Vehicle Speed Signal.
Is vehicle speed displayed on scan tool in step
2) and 3) of DTC confirmation procedure?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Go to Step 4.
4 1) Turn ignition switch to OFF position.
2) Disconnect combination meter connec-
tors.Refer to Section 8.
3) Turn ignition switch to ON position, without
running engine.
4) Measure voltage from terminal “c” of VSS
connector to ground. See Fig.2.
Is voltage within 4 – 5 V?Faulty speedometer.“Y” or “Y/G” wire open or
short.
Poor connection of ECM
connector terminal.
If OK, substitute a known-
good ECM and recheck.
5 1) With ignition switch at OFF position, discon-
nect VSS connector.
2) Turn ignition switch to ON position, without
running engine.
3) Measure voltage from terminal “a” to “b” of
VSS connector. See Fig.1.
Is voltage within 10 – 14 V?Go to Step 6.“Bl/B” or “B/Or” wire open
or short.
6 1) Measure voltage from terminal “c” of VSS
connector to ground. See Fig.2.
Is voltage more than 4 V?Go to Step 7.“Y” or “Y/G” wire open or
short.
Poor connection of ECM
connector terminal.
If OK, substitute a known-
good ECM and recheck.
7 1) Remove VSS.
2) Visually inspect VSS sensor signal rotor for
damage.
Was any damage found?Faulty VSS signal rotor. Poor connection of VSS
connector terminal.
If OK, substitute a known-
good VSS and recheck.
Downloaded from www.Manualslib.com manuals search engine 6-114 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Table B-4 Idle Air Control System Check
INSPECTION
1. Main fuse 2. Fuse box 3. Main relay 4. IAC valve
Step Action Yes No
1 Check engine idle speed and IAC duty referring to
“Idle Speed / IAC Duty Inspection” in Section 6E.
Is idle speed within specification?Go to Step 2. Go to Step 4.
2 Is IAC duty within specification in Step 1? Go to Step 3. Check for followings :
Vacuum leak
EVAP canister purge
control system
Clog of IAC air pas-
sage
Accessory engine
load
Closed throttle posi-
tion (TP sensor)
Stuck of PCV valve
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3 Is engine idle speed kept specified speed even
with headlight ON?System is in good condi-
tion.Check IAC system for
operation referring to
Step 3 or Step 4 of DTC
P0505 Diag. Flow Table.
4 Was idle speed higher than specification in Step
1?Go to Step 5. Go to Step 8.
5 Check A/C (input) signal circuit referring to Step 1
of Table B-5 A/C Signal Circuit Check, if
equipped. (A/C signal can be also checked by
using SUZUKI scan tool.)
Is it in good condition?Go to Step 6. Repair or replace A/C
signal circuit or A/C sys-
tem.
6 Check IAC system referring to Step 2 to Step 4 of
DTC P0505 Diag. Flow Table.
Is check result satisfactory?Go to Step 7. Go to Step 5 of DTC
P0505 Diag. Flow Table.
7 Was IAC duty less than about 3% (or more than
about 97% for OFF duty meter) in Step 1 of this
table?Check abnormal air
inhaling from air intake
system, PCV valve and
EVAP canister purge
control system.Check TP sensor
(closed throttle position)
and ECT sensor for per-
formance.
If sensors are OK, sub-
stitute a known-good
ECM.
8 Is SUZUKI scan tool available? Go to Step 9. Go to Step 10.
9 Check PNP signal (“D” range signal).
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF.
2) Turn ignition switch ON and check PNP signal
(“P/N” and “D” range) on display when shifting
selector lever to each range. See Table 1.
Is check result satisfactory?Go to Step 11. Repair or replace.
10 Check PNP signal (“D” range signal).
1) Turn ignition switch ON.
2) Check voltage at terminal E17-6 of ECM con-
nector connected. See Fig. 1 and Table 1.
Is check result satisfactory?Go to Step 11. Repair or replace.
11 Check IAC system referring to Step 2 to Step 4 of
DTC P0505 Diag. Flow Table.
Is check result satisfactory?Go to Step 12. Go to Step 5 of DTC
P0505 Diag. Flow Table.
12 Was IAC duty more than about 30% or ✱40% (or
less than 70% or ✱60% for OFF duty meter) in
Step 1 of this table? See NOTE.Check parts or system
which can cause engine
low idle.
Accessory engine load
Clog of air passage
Etc.Substitute a known-good
ECM and recheck. Step Action Yes No
NOTE:
Duty value with (
✱
✱✱ ✱) are applicable to vehicle used at high altitude (higher than 2000 m or 6560 ft).
Downloaded from www.Manualslib.com manuals search engine ENGINE AND EMISSION CONTROL SYSTEM 6E-1
6F1
6F2
6G
7C1
7D
7E
7A
7A1
7B1
7C1
7D
7E
7F
8A
8B
8C
8D
6H
6E
10
10A
10B
SECTION 6E
ENGINE AND EMISSION CONTROL SYSTEM
CONTENTS
General Description ....................................... 6E-3
Air Intake System ......................................... 6E-5
Fuel Delivery System ................................... 6E-6
Fuel pump ................................................ 6E-6
Electronic Control System ............................ 6E-7
Engine & emission control input / output
table.......................................................... 6E-8
On-Vehicle Service....................................... 6E-15
Accelerator cable adjustment ................. 6E-15
Idle speed / idle air control (IAC) duty
inspection ............................................... 6E-15
Idle mixture inspection / adjustment
(vehicle without heated oxygen
sensor) ................................................... 6E-17
Air Intake System ....................................... 6E-18
Throttle body .......................................... 6E-18
Idle air control valve (IAC valve)............. 6E-21
Fuel Delivery System ................................. 6E-22
Fuel pressure inspection ........................ 6E-22
Fuel pump .............................................. 6E-23
Fuel pressure regulator .......................... 6E-24
Fuel injector ............................................ 6E-25
Electronic Control System .......................... 6E-29Engine control module (ECM) ................ 6E-29
Manifold absolute pressure sensor (MAP
sensor) ................................................... 6E-29
Throttle position sensor (TP sensor) ...... 6E-30
Intake air temperature sensor
(IAT sensor) ........................................... 6E-31
Engine coolant temperature sensor
(ECT sensor) .......................................... 6E-32
Heated oxygen sensor
(Sensor-1 and sensor-2) ........................ 6E-33
Camshaft position sensor....................... 6E-34
Crankshaft position sensor..................... 6E-35
Vehicle speed sensor (VSS) .................. 6E-36
Fuel level sensor (GAUGE).................... 6E-36
Knock sensor ......................................... 6E-36
Main relay, fuel pump relay and A/C
condenser fan control relay .................... 6E-36
Fuel cut operation .................................. 6E-37
A/C condenser fan control system ......... 6E-37
A/C condenser fan ................................. 6E-37
Output signals of throttle valve opening
and engine coolant temp.
(Vehicle with A/T only) ........................... 6E-38
Emission Control System ........................... 6E-38 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
authorized SUZUKI dealer. Refer to “Air Bag System Components and Wiring Location View” under
“General Description” in air bag system section in order to confirm whether you are performing ser-
vice on or near the air bag system components or wiring. Please observe all WARNINGS and “Ser-
vice Precautions” 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).
NOTE:
Whether following systems (parts) are used in the particular vehicle or not depends on specifications.
Be sure to bear this in mind when performing service work.
EGR valve
Heated oxygen sensor (s) or CO adjusting resistor
Three way catalytic converter (TWC) and warm up three-way catalytic converter (WU-TWC)