ecm SUZUKI GRAND VITARA 2003 2.G Service User Guide

YH4
GRAND
VITARA
SYSTEM CIRCUIT
A. To heater fuse
B. To rear defogger fuse
C. To ignition / meter fuse
D. To A / C fuse
E. Only LH vehicle1. Blower motor relay
2. Blower motor
3. Blower motor switch
4. A / C switch
5. Deflloster position switch
6. Deflloster / foot position switch7. Dual pressure (refrigerant
pressure) switch
8. A / C thermistor (evaporator
temperature sensor)
9. Compressor relay
10. Compressor11. Condenser fan motor relay
12. Condenser fan motor
13. A / C controller
14. ECM
15. Compressor thermal switch
(only IWATA production vehicle)
TERMINAL ARRANGEMENT OF A / C CONTROLLER
TERMINAL ARRANGEMENT OF ECM FOR G16, J20 ENGINE
TERMINAL ARRANGEMENT OF ECM FOR H25 ENGINE
H25 engine
E61-27
G16, J20
engines
E61-8
H25 engine
E61-28
G16, J20
engines
E61-17
1919
19H25 engine
E61-5
G16, J20
engines
E61-22
AIR CONDITIONING (OPTIONAL) 1B-19

YH4
GRAND
VITARA
1B-20 AIR CONDITIONING (OPTIONAL)
A / C CONTROLLER VOLTAGE VALUES TABLE
TerminalWireCircuitMeasurement
groundNormal valueCondition
AC1-1B/WController main
power supplyGround to
engine (Fig. B)10 ± 14 voltsIgnition switch ON with engine
stopped
AC1-2B/YController main
groundGround to body
(Fig. A)± 0.4 ± 0 voltEngine running
AC1 4Or
Refrigerant
p
ressure switchGround to
0 ± 1 volt
Refrigerant pressure within 225 kPa
(2.3 kg / cm
2, 32.7 psi) to 2548 kPa
(26 kg / cm
2, 370 psi) with engine
running
AC1-4Orpressure switch
inputengine (Fig. B)
10 ± 14 volts
Refrigerant pressure below
196 kPa (2.0 kg / cm
2, 28 psi) or
above 3140 kPa (32 kg / cm
2, 455 psi)
with engine running
AC1 7G/B
A / C switch input
and / or defroster
Ground to
8 ± 14 volts
Blower fan motor switch and A / C or
defroster position switch (see NOTE)
ON with engine running
AC1-7G/Bposition switch
input (see NOTE)engine (Fig. B)
0 ± 1.5 volts
Blower fan motor switch or A / C or
defroster position switch (see NOTE)
OFF with engine running
AC1 9Gr/W
Signal input from
ECM (A / C ON
Ground to10 ± 14 voltsApprove of A / C ON
AC1-9Gr/W(
permission
signal)engine (Fig. B)0 ± 1 voltA / C ON forbid
AC1-13Y/B
Signal output to
ECM (A / C ON
request signal)Ground to engine
(Fig. B)0 ± 1.5 volts
Blower fan motor switch and A / C or
defroster position switch (see NOTE)
ON with engine running at evaporator
thermistor temperature input more
than approx. 2.5
C (less than 2.5 V
(5840
)) and refrigerant pressure
switch is ON
10 ± 14 voltsExcept the above-mentioned with
engine running
AC1-16P
Compressor
magnet clutch
relay outputGround to engine
(Fig. B)0 ± 1 volt
Blower fan motor switch and A / C or
defroster position switch ON with
engine running at evaporator
thermistor temperature input more
than approx. 2.5
C (less than 2.5 V
(5840
)), refrigerant pressure
switch ON and signal input from ECM
ON
10 ± 14 voltsExcept the above-mentioned with
engine running

YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-21
TerminalWireCircuitMeasurement
groundNormal valueCondition
AC2-1L/YSensor groundGround to body
(Fig. A)± 0.4 ± 0 voltEngine running
1.5 volts
(3150
)Evaporator thermistor temperature at
approx. 15C (59F) with engine
running
AC2-2W/B
Evaporator
thermistor
temperature
(evaporator temp.
sensor) input
Ground to engine
(Fig. B)
2.62 volts
(6.311
)
Evaporator thermistor temperature at
approx. 1C (34F) with engine
running
* If the temperature is less than
approx. 1C, in this case
compressor and condenser fan
should be stop (come back at more
than approx. 2.5C (less than
5840
, 2.5 V))
H25
engine
E61-27 /
G16 J20Gr/W
Signal output to
A / C controller
(A / C ON
Ground to engine
(Fig C)
10 ± 14 volts
Required A / C ON (terminal AC-A13)
at engine running with normal
condition (refer to ªINSPECTION OF
ECM AND ITS CIRCUITº in Section
6E)
G16, J20
engines
E61-8
(
permission
signal)(Fig. C)
0 ± 1 volt
Except the above-mentioned with
engine running
In this case compressor should be
stop
H25
engine
E61-28 /
Y/B
Signal input from
A / C controller
Ground to engine
0 ± 1.5 voltsRequire A / C ON
G16, J20
engines
E61-17Y/B(A / C ON request
signal)
g
(Fig. C)
10 ± 14 voltsTurn off the A / C
H25
engine
E61-5 /
G16, J20
engines
E61-22
Y/L
A / C condenser
cooling fan relay
outputGround to engine
(Fig. C)0 ± 1 volt

Blower fan motor switch and A / C or
defroster position switch (see
NOTE) ON with engine running at
evaporator thermistor temperature
input more than approx. 2.5C (less
than 2.5 V (5840
)), refrigerant
pressure switch ON and signal
input from ECM ON

Engine coolant temperature sensor
more than 113C (236F) with
engine running
10 ± 14 voltsExcept the above-mentioned with
engine running
NOTE:
Defroster position switch circuit is equipped with LH vehicle only.

YH4
GRAND
VITARA
1. Suction connector
2. O-ring
3. Pressure switch
4. Flow control valve
(Relief valve)
5. Spring
6. Plug
7. Pump cover
8. Cam ring
9. Vane
10. Rotor
11. Snap ring
12. Side plate
13. Pulley (pump shaft)
14. Oil seal
15. Pump body
16. Flow control valve Assembly
3B1-4 POWER STEERING (P / S) SYSTEM
POWER STEERING (P / S) PUMP
The power steering pump is a vane type and is driven by the V-ribbed belt from the crankshaft.
ModelVane type
Hydraulic
pressure
controlRelieved
pressure
6500 kPa (65 kg / cm2, 924 psi)
G16 Type engine . . . . . . . . . . . . . . . . . . . . . .
7000 kPa (70 kg / cm
2, 995 psi)
J20 Type engine . . . . . . . . . . . . . . . . . . . . . . .
7350 kPa (73.5 kg / cm
2, 1045 psi)
H25 Type engine . . . . . . . . . . . . . . . . . . . . . .
ControlFlow control valve
deviceRelief valve
Power steering
pressure switch
Switch turns on (closes) when the
pressure is higher than 2500 ± 3500 kPa
(25 ± 35 kg / cm
2, 356 ± 498 psi).
ECM uses this signal for idle speed control.
Capacity0.70 ± 0.75

(1.48 / 1.23 ± 1.58 / 1.32 US / Imp. pt)
Specified fluidDEXRON
II, DEXRON
III A / T fluid
or equivalent
FLOW CONTROL VALVE
As the discharge rate of the P/S pump increases in proportion to the
pump revolution speed, a flow control valve is added to control it so
that the optimum amount of fluid for steering operation is supplied
according to the engine speed (driving condition).
Described below is its operation at different engine speed.

YH4
GRAND
VITARA
1. Wheel speed sensor (Right-front)
2. Stop lamp switch
3. ABS control module
4. Wheel speed sensor (Right-rear)
5. Diagnosis connector
6. Data link connector7. Wheel speed sensor (Left-rear)
8. ªABSº warning lamp
9. ABS pump motor relay
10. ABS fail-safe relay (Solenoid valve relay)
11. Lamp drive module
12. Wheel speed sensor (Left-front)13. ABS hydraulic unit
14. G sensor (For 4WD model only)
15. 4WD switch (For 4WD model only)
16. ABS hydraulic unit / control module assembly
(with ABS pump motor & fail-safe relays)
17. ªEBDº warning lamp (Brake warning lamp)
Wheel speed sensor (LR)
Wheel speed sensor (LF)
Wheel speed sensor (RF)
Wheel speed sensor (RR)
Stop lamp switch
G sensor (For 4WD model only)
Diag. switch terminal
Battery Voltage
4WD switch (For 4WD model only)
Pump motor relay
Pump motor
LF inlet solenoid
LF outlet solenoid
LR inlet solenoid
LR outlet solenoid
Rear inlet solenoid
Rear outlet solenoid
ªABSº warning lamp
Brake warning lamp
Data link connector
Fail-safe relay
Hydraulic unit
OUTPUTINPUT
ABS control
module
ABS hydraulic unit / control
module assembly
PCM or ECMIdle up
5E1-4 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
SYSTEM SCHEMATIC

YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-15
1. Battery
2. Main fuses
3. Ignition switch
4. Circuit fuses
5. ABS hydraulic unit / control module
5-1. Terminal arrangement for ABS hydraulic unit /
control module assembly
5-2. ABS fail-safe relay (Solenoid valve relay)
5-3. ABS pump motor relay
5-4. Pump motor
5-5. Solenoid valves
6. ªABSº warning lamp
7. Right-rear wheel speed sensor
8. Left-rear wheel speed sensor
9. Right-front wheel speed sensor
10. Left-front wheel speed sensor
11. Data link connector
12. Diagnosis connector
13. Stop lamp
14. Stop lamp switch
15. PCM (ECM+TCM) or ECM
16. G sensor (For 4WD model only)
17. 4WD switch (For 4WD model only)
18. 4WD indicator lamp (For 4WD model only)
19. 4WD controller (If equipped)
20. EBD warning lamp (Brake warning lamp)
21. Combination meter
22. Parking brake switch
23. Brake fluid lever switch
24. Warning lamp driver moduleWire colorB : Black
B / Bl : Black / Blue
B / O : Black / Orange
B / W : Black / White
Bl : Blue
Bl /B : Blue / Black
Bl / O : Blue / Orange
Br : Brown
G : Green
G / B : Green / Black
G / W : Green / White
Lg : Lightgreen
Lg / B : Lightgreen / Black
O / B : Orange / Black
O / G : Orange / Green
O / W : Orange / White
P : Pink
P / B : Pink / Black
V / G : Violet / Green
W / BI : White / Blue
W / G : White / Green
W / Y : White / Yellow
Y : Yellow
Y / B : Yellow / Black
SYSTEM CIRCUIT
TERMINALCIRCUIT
A1Right-rear wheel speed sensor (+)
A2Right-front wheel speed sensor (±)
A3Right-front wheel speed sensor (+)
A4G sensor ground (For 4WD model only)
A5ÐÐÐ
A6ÐÐÐ
A7Idle up signal
A8Diagnosis switch terminal
A9Stop lamp switch
A10Ground (For ABS control module)
A11ABS fail-safe relay
A12Right-rear wheel speed sensor (±)
A13Left-front wheel speed sensor (±)
A14G sensor signal (For 4WD model only)
A15ÐÐÐ
A16ÐÐÐ
A17ªABSº warning lamp
A18Left-rear wheel speed sensor (+)
A19Left-rear wheel speed sensor (±)
A20Left-front wheel speed sensor (+)
A21ÐÐÐ
A22Data link connector
A23ÐÐÐ
A244WD switch (For 4WD model only)
A25Ignition switch
A26ªEBDº warning lamp
A27ABS pump motor relay
A28Ground (For ABS pump motor)

YH4
GRAND
VITARA
7B1-8 AUTOMATIC TRANSMISSION (4 A / T)
G16 / J20 Engines
1. PCM (ECM)
2. VSS
3. CMP sensor
4. TP sensor
5. ECT sensor
6. A / T input speed sensor
7. A / T output speed sensor
8. Transmission range switch9. Shift solenoid-A
10. Shift solenoid-B
11. TCC solenoid
12. Data link connector
13. Cruise control module
14. ªPOWERº lamp
15. ªO / D OFFº lamp
16. MIL17. O / D cut switch
18. P / N change switch
19. 4WD low switch
20. Main relay
21. Ignition switch
22. Battery
23. PCM (ECM) connector terminal
(viewed from harness side) Bl / Y
Bl / G
W
OrC51-1-11
C51-1-10
C51-1-23
C51-1-22
12V

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-9
H25 Engine
1. PCM (ECM)
2. VSS
3. CMP sensor
4. TP sensor
5. ECT sensor
6. Brake pedal switch
7. A / T input speed sensor
8. A / T output speed sensor9. Transmission range switch
10. Shift solenoid-A
11. Shift solenoid-B
12. TCC solenoid
13. Data link connector
14. Cruise control module
15. ªPOWERº lamp
16. ªO / D OFFº lamp17. MIL
18. O / D cut switch
19. P / N change switch
20. 4WD low switch
21. Main relay
22. Ignition switch
23. Battery
24. PCM (ECM) connector terminal
(viewed from harness side) Bl / Y
Bl / G
W
OrC51-1-16
C51-1-8
C51-1-10
C51-1-9
12V

YH4
GRAND
VITARA
1. Monitor connector
AUTOMATIC TRANSMISSION (4 A / T) 7B1-17
AUTOMATIC TRANSMISSION DIAGNOSIS
This vehicle is equipped with an electronic transmission control system, which control the automatic shift up and
shift down timing, TCC operation, etc. suitably to vehicle driving conditions.
PCM (ECM) has an On-Board Diagnosis system which detects a malfunction in this system and abnormality of
those parts that influence the engine exhaust emission.
When diagnosing a trouble in transmission including this system, be sure to have full understanding of the outline
of ªOn-board Diagnostic Systemº and each item in ªPrecaution in Diagnosing Troubleº and execute diagnosis ac-
cording to ªAUTOMATIC TRANSMISSION DIAGNOSTIC FLOW TABLEº given below to obtain correct result
smoothly.
NOTE:
There are two types of ON-BOARD DIAGNOSTIC SYSTEM de-
pending on vehicle specifications. The type of system for ve-
hicle being serviced can be identified by whether equipped
with monitor connector or not.

YH4
GRAND
VITARA
1. Malfunction indicator lamp (MIL)
2. Scan tool
3. DLC
7B1-18 AUTOMATIC TRANSMISSION (4 A / T)
[For Vehicle without Monitor Connector]
ON-BOARD DIAGNOSTIC SYSTEM
For automatic transmission control system, PCM (ECM) has follow-
ing functions. Refer to Section 6 / 6-1 for details.

When the ignition switch is turned ON with the engine at a stop,
malfunction indicator lamp (MIL) turns ON to check the bulb of the
MIL.

When PCM detects a malfunction in A / T control system (and / or
a malfunction which gives an adverse effect to vehicle emission)
while the engine is running, it makes the malfunction indicator
lamp in the meter cluster of the instrument panel turn ON and
stores the malfunction area in its memory. (If it detects that contin-
uously 3 driving cycles are normal after detecting a malfunction,
however, it makes MIL turn OFF although DTC stored in its
memory will remain.)

It is possible to communicate through DLC by using not only SU-
ZUKI scan tool (Tech-1) but also generic scan tool. (Diagnostic in-
formation can be accessed by using a scan tool.)
2 Driving Cycle Detection Logic
Refer to section 6 / 6-1 for details.
Pending DTC
Refer to section 6 / 6-1 for details.
Freeze Frame Data
Refer to section 6 / 6-1 for details.