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Table B-5 A/C Signal Circuits Check (Vehicle with A/C)
1. A/C compressor magnet clutch 4. A/C condenser fan 7. Evaporator temp. sensor
2. A/C switch 5. Refrigerant pressure switch [A] : Case of TYPE A is shown (See NOTE)
3. Blower fan 6. ECT sensor [B] : Case of TYPE B is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
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INSPECTION
Fig. 1 for Step 1Step Action Yes No
1 Check evaporator temp. sensor.
1) Disconnect ECM connectors with ignition
switch at OFF position.
2) Check resistance between E19-14 terminal
and E19-10 terminal.
Reference value
(Refer to characteristic curve below)
ECT sensor resistance
At 0°C 6.3 – 6.9 k
Ω
ΩΩ Ω
At 25°C 1.8 – 2.2 k
Ω
ΩΩ Ω
Is it within specification?Go to Step 2. Faulty A/C evaporator
thermistor or its circuit.
2 Check A/C switch circuit.
1) Check voltage at E18-16 terminal under
each condition given below.
A/C switch signal specification
Ignition switch ON A/C switch OFF
: 10 – 14 V
Ignition switch ON A/C switch ON
: 0 – 1 V
Is check result satisfactory?Go to Step 3.“G/W” wire open or short
Poor E18-16 terminal con-
nection
If wire and connection are
OK, substitute a known-
good ECM and recheck.
Go to Step 3.
3 Check A/C compressor signal.
1) Check voltage at E18-1 terminal under each
condition given below. See NOTE.
A/C compressor signal specification
While engine running, A/C switch OFF
: 0 V
While engine running, A/C switch ON
: 10 – 14 V
Is check result satisfactory?A/C control system cir-
cuits are in good condi-
tion.“P” wire open or short
Poor E18-1 terminal con-
nection
If wire and connection are
OK, substitute a known-
good ECM and recheck.
NOTE:
When A/C evaporator thermistor temp. is below 2.5 °C (36.5 °F), A/C remain OFF (E18-1 terminal volt-
age become 0 – 1 V). This condition is not abnormal.
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Table B-6 Electric Load Signal Circuit Check
INSPECTION
1. Rear defogger switch 3. Blower fan switch [B] : Case of TYPE B is shown (See NOTE)
2. Light switch [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.
Step Action Yes No
1 Is SUZUKI scan tool available? Go to Step 2. Go to Step 3.
2 Check Electric Load Signal Circuit.
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF. See Fig.1.
2) Start engine and select “DATA LIST” mode
on scan tool.
3) Check electric load signal under following
each condition. See Table 1.
Is check result satisfactory?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.
3 Check Electric Load Signal Circuit.
1) Turn ignition switch ON.
2) Check voltage at each terminals E17-16,
E18-17 and E18-24 (Case of TYPE A) or
E18-12, E18-17 and E17-13 (Case of TYPE
B) (See NOTE) of ECM connector con-
nected, under above each condition. See
Fig. 2. and Table 1.
Is each voltage as specified?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.
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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)
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General Description
The engine and emission control system is divided into 4 major sub-systems: air intake system, fuel delivery
system, electronic control system and emission control system.
Air intake system includes air cleaner, throttle body, IAC valve and intake manifold.
Fuel delivery system includes fuel pump, delivery pipe, fuel pressure regulator, etc. Electronic control system
includes ECM, various sensors and controlled devices.
Emission control system includes EGR, EVAP and PCV system.
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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)
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Fuel Delivery System
The fuel delivery system consists of the fuel tank (1), fuel pump (2), fuel filter (3), fuel pressure regulator (11),
delivery pipe (9) and fuel injectors (10).
The fuel in the fuel tank is pumped up by the fuel pump, filtered by the fuel filter and fed under pressure to each
injector through the delivery pipe.
As the fuel pressure applied to the injector (the fuel pressure in the fuel feed line) is always kept a certain
amount higher than the pressure in the intake manifold by the fuel pressure regulator, the fuel is injected into the
intake port of the cylinder head when the injector open according to the injection signal from ECM.
The fuel relieved by the fuel pressure regulator returns through the fuel return line (8) to the fuel tank.
Fuel pump
An in-tank type electric pump has been adopted for the fuel pump
(1). Incorporated in the pump assembly are;
Tank pressure control valve (2) which keeps the pressure in
the fuel tank constant, and prevents the fuel from spouting
and tank itself from being deformed.
Relief valve (3) which prevents the pressure in tank from ris-
ing excessively.
Fuel cut valve (4) which closes as the float rises so that the
fuel will not enter the canister when the fuel level in the tank
rises high depending on the fuel level in the tank and the
vehicle tilt angle.
Also, a fuel filter (5) is included and a fuel level gauge (6) is
attached.
4. Fuel cut valve 6. To EVAP canister 12. To intake manifold (vacuum passage)
5. Fuel tank pressure control valve 7. Fuel feed line
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Electronic Control System
The electronic control system consists of 1) various sensors which detect the state of engine and driving condi-
tions, 2) ECM which controls various devices according to the signals from the sensors and 3) various controlled
devices.
Functionally, it is divided into the following sub systems:
Fuel injection control system
Idle speed control system
Fuel pump control system
A/C control system (if equipped)
A/C condenser fan control system
EGR system (if equipped)
Evaporative emission control system
Oxygen sensor heater control system
Ignition control system
Also, with A/T model, ECM sends throttle valve opening signal and over drive cut signal to transmission control
module to control A/T.
NOTE:
The figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are installed
at the other side.
1. IAT sensor a : Immobilizer indicator lamp (if equipped) A : ECM
2. TP sensor b : A/C condenser fan motor relay (if equipped) B : A/T control module
3. Monitor connector c : Main relay C : EVAP canister
4. CO adjusting resistor (if equipped) d : Fuel pump relay D : DLC
5. CKP sensor e : IAC valve E : ABS control module (if equipped)
6. MAP sensor f : EVAP canister purge valve
7. CMP sensor g : EGR valve (if equipped)
8. Transmission range switch h : Fuel injector
9. VSS i : Ignition coil assemblies
10. HO2S-1 (if equipped) J : MIL
11. HO2S-2 (if equipped)
12. ECT sensor
13. Knock sensor