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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.
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[A] Fig. 1 for Step 3 / [B] Fig. 2 for Step 3 / [C] Fig. 3 for Step 4 / [D] Fig. 4 for Step 5 / [E] Fig. 5 for Step 47 Check EVAP Canister Purge Valve for Closing.
1) Disconnect purge hose (1) from EVAP canister.
2) Place finger against the end of disconnected hose.
3) Check that vacuum is not felt there, when engine is
cool and running at idle. See Fig. 7.
Is vacuum felt?Check EVAP control
system
(See Section 6E).Go to Step 8.
8 Check manifold absolute pressure sensor for perfor-
mance (See step 4) DTC P0105 Diag. Flow Table).
Is it in good condition?Go to Step 9. Repair or replace.
9 Check engine coolant temp. sensor for performance
(See Section 6E).
Is it in good condition?Go to Step 10. Replace engine
coolant temp. sen-
sor.
10 Check parts or system which can cause engine rough
idle or poor performance.
Engine compression (See Section 6A1).
Valve lash (See Section 6A1).
Valve timing (Timing belt installation. See Section
6A1).
Are they in good condition?Check wire harness
and connection of
ECM ground, ignition
system and fuel injec-
tor for intermittent
open and short.Repair or replace. Step Action Yes No
CAUTION:
For iridium spark plugs, do not adjust air gap or clean.
3. Fuel delivery pipe
4. Fuel feed hose
3. Fuel pressure gauge & 3 way joint
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DTC P0400 Exhaust Gas Recirculation Flow Malfunction
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, 122 °F or lower
1. EGR valve
DTC DETECTING CONDITION POSSIBLE CAUSE
While running at specified vehicle speed after engine warm-up
During deceleration (engine speed high with closed throttle position
ON) in which fuel cut is involved, difference in intake manifold absolute
pressure between when EGR valve is opened at specified value and
when it is closed is larger or smaller than specified value.
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 drivingEGR valve or its circuit
EGR passage
ECM
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.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-99
DTC P1450 Barometric Pressure Sensor Low / High Input
DTC P1451 Barometric Pressure Sensor Performance Problem
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Barometric pressure sensor is installed in ECM.
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Turn ignition switch ON for 2 sec., crank engine for 2 sec. and run it at idle for 1 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
DTC P1450 :
Substitute a known-good ECM and recheck.
DTC P1451 :
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC P1450 :
Barometric pressure sensor voltage is 4.7 V or higher, or
1.6 V or lowerECM (barometric pressure sensor) malfunc-
tion
DTC P1451 :
Vehicle stopped
Engine cranking
Difference between barometric pressure and intake mani-
fold absolute pressure is 26 kPa, 200 mmHg or more.
Difference between intake manifold absolute pressure at
engine start and pressure after engine start is less than 1.3
kPa, 10 mmHg.
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 driving.ECM (barometric pressure sensor) malfunc-
tion
NOTE:
Note that atmospheric pressure varies depending on weather conditions as well as altitude.
Take that into consideration when performing these check.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) Connect scan tool to DLC with ignition
switch OFF. See Fig.1.
2) Turn ignition switch ON and select “DATA
LIST” mode on scan tool.
3) Check manifold absolute pressure.
Is it barometric pressure (approx. 100 kPa, 760
mmHg) at sea level?Substitute a known-good
ECM and recheck.Go to Step 3.
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[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 3
Table 13 Check MAP Sensor
1) Remove MAP sensor from intake manifold
and connect vacuum pump gauge to MAP
sensor. See Fig. 2.
2) Connect scan tool to DLC and turn ignition
switch ON.
3) Check intake manifold absolute pressure
displayed on scan tool for specified value.
See Table 1.
Is check result satisfactory?Check air intake system
for air being drawn in and
engine compression.
If OK, then substitute a
known-good ECM and
recheck.Replace MAP sensor. Step Action Yes No
Applying Vacuum Displayed Value on Scan Tool
0 Barometric pressure
(Approx. 100 kPa, 760 mmHg)
027 kPa
200 mmHgBarometric pressure – 27 kPa
(Approx. 73 kPa, 560 mmHg)
67 kPa
500 mmHgBarometric pressure – 67 kPa
(Approx. 33 kPa, 260 mmHg)
Downloaded from www.Manualslib.com manuals search engine 6-104 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P1570 (DTC No.21) ABS Signal Circuit Malfunction
CIRCUIT DESCRIPTION
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.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
ABS signal input is low when engine start.ABS signal circuit short to ground
ABS control module
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) With the ignition switch ON position, check
voltage between E17-12 terminal of ECM
coupler and ground.
Is voltage within 10 – 14 V?Intermittent trouble.
If OK, substitute a known-
good ECM and recheck.Go to Step 3.
3 1) Check “G” wire for shorted to ground circuit.
Is “G” wire in good condition?Go to Step 4. Repair or replace.
4 1) Disconnect coupler of ABS control module.
2) Clear DTC.
3) Start engine and check DTC.
Is DTC P1570 (No.21) detected?Substitute a known-good
ECM and recheck.Substitute a known-good
ABS control module and
recheck.
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)
Downloaded from www.Manualslib.com manuals search engine ENGINE AND EMISSION CONTROL SYSTEM 6E-5
Air Intake System
The main components of the air intake system are air cleaner (1), air cleaner outlet hose (2), throttle body (3),
idle air control valve (4) and intake manifold (5).
The air (by the amount corresponding to the throttle valve (6) opening and engine speed) is filtered by the air
cleaner (1), passes through the throttle body (3), is distributed by the intake manifold (5) and finally drawn into
each combustion chamber.
When the idle air control valve (4) is opened according to the signal from ECM, the air (7) bypasses the throttle
valve (6) through bypass passage and is finally drawn into the intake manifold (5).
1. Air Cleaner 17. Knock sensor 31-2. Test switch terminal
(vehicle w/o immobilizer indicator lamp)
2. EVAP canister purge valve 18. ECT sensor 31-3. Duty output terminal
(vehicle w/o immobilizer indicator lamp)
3. IAT sensor 19. CMP sensor 32. Immobilizer indicator lamp (if equipped)
4. TP sensor 20. CKP sensor 33. Stop lamp switch
5. IAC valve 21. VSS 34. ECM
6. MAP sensor 22. A/C condenser fan (if equipped) 35. Barometric pressure sensor
(vehicle with immobilizer indicator lamp)
7. EGR valve (if equipped) 23. Malfunction indicator lamp in combination meter 36. Battery
8. EVAP canister 24. Park/Neutral position switch in TR switch (A/T) 37. Immobilizer control module (if equipped)
9. Tank pressure control valve (built-in fuel pump) 25. Ignition switch 38. ABS control module (if equipped)
10. Fuel pump 26. Starter magnetic switch 39. CO adjusting resistor (if equipped)
11. Fuel level sensor 27. TCM (A/T) 40. Power steering pressure switch
(if equipped)
12. Ignition coil assembly 28. Transmission range switch (A/T) 41. A/C compressor clutch (if equipped)
13. Fuel injector 29. DLC 42. A/C EVAP TEMP. sensor (if equipped)
14. Heated Oxygen Sensor (HO2S)-1 (if equipped) 30. Electric load 43. A/C switch (if equipped)
15. Heated Oxygen Sensor (HO2S)-2 (if equipped) 31. Monitor connector (if equipped)
16. Three way catalytic convertor (if equipped) 31-1. Diagnosis switch terminal
(vehicle w/o immobilizer indicator lamp)