1999 SUZUKI GRAND VITARA ecm wiring

YH4
GRAND
VITARA
1A-4 HEATER AND VENTILATION
FOR LH VEHICLE
FOR RH VEHICLE
1. From ignition switch 1
2. From ignition switch 2
3. From blower fuse
4. Head light relay
5. To A / C controller6. Blower motor relay
7. Blower motor switch
8. Blower resistor
9. Blower motor
10. To ECM11. To illumination controller
(if equipped) or body ground
12. Mode control actuator
13. Mode control switch
14. From main fuse15. TAIL fuse 15 A
16. IG METER fuse 20 A
17. HEATER fuse 30 A
18. REAR DEFG fuse 15 A
19. Drive circuit
WIRING CIRCUIT

YH4
GRAND
VITARA
1B-6 AIR CONDITIONING (OPTIONAL)
DIAGNOSIS
GENERAL
ConditionPossible CauseCorrection
Cool air won't come out
(A / C system won't
operative)
No refrigerant

Fuse blown

A / C switch faulty

Blower motor switch faulty

A / C thermistor faulty

Dual pressure switch faulty

Wiring or grounding faulty

A / C ON permission signal in ECM
faulty

A / C controller and its circuit faultyRecover, evacuation and charging.
Check ªIG METERº fuse, ªREAR DEFGº
fuse, and ªA / C FUSEº and check for
short circuit to ground.
Check A / C switch.
Check blower motor switch.
Check A / C evaporator thermistor.
Check dual pressure switch.
Repair as necessary.
Check ON permission signal.
Check A / C controller and its circuit.
Cool air won't come out
(A / C compressor won't
operative)
Magnet clutch faulty

Compressor relay faulty

Compressor thermal switch faulty
(if equipped)

Drive belt loose or broken

Compressor faulty

A / C ON permission signal in ECM
faulty

A / C controller faultyCheck magnet clutch.
Check compressor thermal switch.
Check compressor relay.
Adjust or replace drive belt.
Check compressor.
Check ON permission signal.
Check A / C controller.
Cool air won't come out
(A / C condenser cooling
fan motor won't
operative)
Condenser cooling fan relay faulty

Wiring or grounding faulty

ªA / C condenser cooling fan relayº
signal in ECM faulty

Condenser cooling fan motor faultyCheck condenser cooling fan relay.
Repair as necessary.
Check A / C condenser cooling fan relay
signal.
Check condenser cooling fan motor.
Cool air won't come out
(Blower motor won't
operative)
Fuse blown

Blower motor relay faulty

Blower motor resistor faulty

Blower motor switch faulty

Wiring or grounding faulty

Blower motor faultyCheck ªHEATER FUSEº, ªREAR DEFGº
fuse and check for short circuit to
ground.
Check blower motor relay.
Check blower motor resistor.
Check blower motor switch.
Repair as necessary.
Check blower motor.
Cool air won't come out
or insufficient cooling
(A / C system normal
operative)
Insufficient or excessive charge of
refrigerant

Refrigerant leak in system

Condenser clogged

A / C evaporator clogged or frosted

A / C thermistor faulty

A / C controller faulty

Expansion valve faulty

Drive belt slipping

Magnetic clutch faultyCheck charge of refrigerant.
Check system for leaks.
Check condenser.
Check A / C evaporator.
Check A / C thermistor.
Check A / C controller.
Check expansion valve.
Check or replace drive belt.
Check magnetic clutch.

YH4
GRAND
VITARA
1. Blower motor main relay
2. Blower motor
3. Blower motor resistor
4. Blower motor switch
5. A / C controller
6. ECM
7. Heater mode control switch
8. Evaporator temperature sensor
9. Refrigerant pressure switch10. Compressor relay
11. Compressor
12. Condenser cooling fan relay
13. Condenser cooling fan
14. Fuse box
15. A / C fuse 25 A
16. Ignition switch
17. Main fuse box
18. Battery main fuse 80 A19. Battery
20. Generator
21. Ignition main fuse 60 A
22. Heater/A/C main fuse 60 A
23. Ignition / meter fuse 20 A
24. Rear defogger fuse 15 A
25. Heater fuse 30 A
26. Compressor thermal switch
(only IWATA production vehicle)
FOR LH VEHICLE
1B-16 AIR CONDITIONING (OPTIONAL)
WIRING CIRCUIT

YH4
GRAND
VITARA
Fig. A
Fig. B
Fig. C
C51-3-6 For G16
and J20 engines
C51-3-25 For
H25 engine
1B-18 AIR CONDITIONING (OPTIONAL)
INSPECTION OF A / C CONTROLLER AND ITS
CIRCUITS
CAUTION:
A / C controller and ECM cannot be checked by itself.
It is strictly prohibited to connect voltmeter or ohmmeter to
A / C controller and ECM with couplers disconnected from it.
A / C controller (1) and its circuits can be checked at A / C controller
wiring couplers by measuring voltage.
Voltage Check
1) Remove A / C controller (1) from vehicle (refer to ªA / C CON-
TROLLER REMOVALº in this section).
2) Remove ECM (2) from vehicle.
3) Connect A / C controller couplers to A / C controller and connect
ECM couplers to ECM.
4) Check each terminal voltage with couplers connected by refer-
ing to the A / C CONTROLLER VOLTAGE VALUES TABLE the
later.

YH4
GRAND
VITARA
8G
IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED) 8G-1
GENERAL DESCRIPTION8G- 2 . . . . . . . . . . . . . .
Ignition Key 8G- 3. . . . . . . . . . . . . . . . . . . . . . . . . .
Coil Antenna 8G- 3. . . . . . . . . . . . . . . . . . . . . . . . .
Immobilizer Control Module 8G- 4. . . . . . . . . . . .
ECM/PCM 8G- 4. . . . . . . . . . . . . . . . . . . . . . . . . . .
On-Board Diagnostic System
(Self-Diagnosis Function) 8G- 4. . . . . . . . . . . . .
DIAGNOSIS8G- 6 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Precautions in Diagnosing Troubles 8G- 6. . . . .
Diagnostic Flow Table with monitor coupler> 8G- 9. . . . . . . . . . . . . . . .
Diagnostic Flow Table equipped with monitor coupler> 8G-10. . . . . . .
Diagnostic Trouble Code Check
(Immobilizer Control Module) 8G-11. . . . . . . .
Diagnostic Trouble Code Check
(ECM / PCM) 8G-11. . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code Table 8G-13. . . . . . . . .
TABLE A DTC is not Output
from Diagnostic Output Terminal 8G-14. . . . . . .
TABLE B Immobilizer Indicator Lamp
Check (Immobilizer Indicator Lamp
does not Light at Ignition Switch ON) 8G-15. . .
TABLE C Immobilizer Indicator Lamp
Check (Immobilizer Indicator Lamp
Remains on after Engine Starts) 8G-16. . . . . . .
DTC11 Transponder Code Not Matched8G-17 . .
DTC31 Transponder Code Not
Registered 8G-17. . . . . . . . . . . . . . . . . . . . . . . . .
DTC12 Fault in Immobilizer
Control Module 8G-17. . . . . . . . . . . . . . . . . . . . . .
DTC13 No Transponder Code Transmitted
or Coil Antenna Opened/Shorted 8G-18. . . . . . DTC21 ECM/Immobilizer Control Module
Code Not Matched (Immobilizer Control
Module Side) 8G-20. . . . . . . . . . . . . . . . . . . . . . .
DTC81 (P1623) ECM/Immobilizer
Control Module Code Not Matched
(ECM/PCM Side) 8G-20. . . . . . . . . . . . . . . . . . . .
DTC84 (P1620) ECM/Immobilizer Control
Module Code Not Registered 8G-20. . . . . . . . .
DTC22 Ignition Switch Circuit Open/Short8G-21 . .
DTC23 No ECM/Immobilizer Control
Module Code Transmitted from ECM/
PCM or DLC Circuit Opened/Shorted8G-22 . . . .
DTC83 (P1621) No ECM/Immobilizer
Control Module Code Transmitted from
Immobilizer Control Module or DLC
Circuit Opened/Shorted 8G-22. . . . . . . . . . . . . .
DTC82 (P1622) Fault in ECM/PCM 8G-23. . . . .
Inspection of ECM/PCM, Immobilizer
Control Module and Its Circuit 8G-24. . . . . . . . .
Voltage Check 8G-24. . . . . . . . . . . . . . . . . . . . .
Resistance Check 8G-25. . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE8G-26 . . . . . . . . . . . . . . . .
Precautions in Handling Immobilizer
Control System 8G-26. . . . . . . . . . . . . . . . . . . . .
Immobilizer Control Module 8G-27. . . . . . . . . . . .
Coil Antenna 8G-27. . . . . . . . . . . . . . . . . . . . . . . . .
HOW TO REGISTER IGNITION KEY8G-28 . . . . .
PROCEDURE AFTER IMMOBILIZER
CONTROL MODULE REPLACEMENT8G-29 . .
PROCEDURE AFTER ECM/PCM
REPLACEMENT8G-30 . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS8G-30 . . . . . . . . . . . . . . . . . . . . . .
SECTION 8G
IMMOBILIZER CONTROL SYSTEM
(IF EQUIPPED)
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 ªAir Bag System Components and Wiring Location Viewº under ªGener-
al Descriptionº 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 ªService Precau-
tionsº under ªOn-Vehicle Serviceº 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
ªLOCKº 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

YH4
GRAND
VITARA
8G-24 IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED)
1
2
3
1
2
1. Immobilizer Control Module
2. Immobilizer Control Module Coupler
3. Body ground
INSPECTION OF ECM / PCM, IMMOBILIZER
CONTROL MODULE AND ITS CIRCUIT
ECM / PCM, Immobilizer Control Module and its circuit can be
checked at ECM / PCM wiring couplers and Immobilizer Control
Module wiring coupler by measuring voltage and resistance. De-
scribed here is only inspection of Immobilizer Control Module. For
inspection of ECM / PCM, refer to ªSECTION 6E1 or 6E2º.
CAUTION:
Immobilizer Control Module cannot be checked by itself. It
is strictly prohibited to connect voltmeter or ohmmeter to
Immobilizer Control Module with coupler disconnected
from it.
Voltage Check
1) Remove Immobilizer Control Module from body with ignition
switch OFF, referring to p. 8G-24.
2) Connect Immobilizer Control Module coupler to Immobilizer
Control Module.
3) Check voltage at each terminal of coupler connected.
NOTE:
As each terminal voltage is affected by the battery voltage,
confirm that it is 11 V or more when ignition switch is ON.
TERMINALCIRCUITNORMAL
VOLTAGECONDITION
A1Coil antenna 10 V
A2Coil antenna 20 VIgnition switch ON
A3Power source10 ± 14 V
A4Ignition signal10 ± 14 VIgnition switch ONA4Ignition signal0 ± 0.8 VIgnition switch OFF
A5Diagnosis output0 ± 14 VIgnition switch ONA5Diagnosis output0 VIgnition switch OFF
A6Blank±±
A7Ground±±
A8Data link connector
(Serial data terminal)4 ± 5 VIgnition switch ON
A9
A10Blank±±
NOTE:
When measuring voltage at A1 and A2 terminals with ignition switch turned ON, be sure to turn ignition
switch ON before connecting positive probe of voltmeter to A1 or A2 terminal. If it is not turned ON first,
DTC13 (Diagnostic Trouble Code 13) may be indicated.

YH4
GRAND
VITARA
WIRE HARNESS COLOR
B : Black
B/W : Black/White
Bl : Blue
Bl/B : Blue/Black
Bl/R : Blue/Red
Br : BrownG : Green
Gr : Gray
G/R : Green/Red
Lg : Lightgreen
P : Pink
V : VioletY : Yellow
Y / G : Yellow/Green
Y/R : Yellow/Red
W : White
W/B : White/Black
1. From main fuse
2. Ignition switch
3. ªIG
.COIL METERº fuse in J/B
4. ªAIR BAGº warning lamp in combination meter
5. ªAIR BAGº fuse in ªAIR BAGº fuse box
6. Connection detection pin
7. To ECM (or PCM), ICM (if equipped) and ABS
controller (if equipped)
8. To data link connector (DLC)
9. ªAIR BAGº monitor coupler
10. SDM
11. Contact coil assembly
12. Driver air bag (inflator) module
13. Driver seat belt pretensioner (if equipped)
14. Passenger air bag (inflator) module
15. Passenger seat belt pretensioner (if equipped)
16. Pretensioner harness (if equipped)
17. Ground for air bag system
TERMINAL
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A13 A11
A12
A14
A15
A16
Passenger air bag (inflator) moduleLow
High
CIRCUIT
Data link connector (DLC)
Low
High
Low
High
Low
High ªAIR BAGº warning lamp
Driver air bag (inflator) module
Diagnosis switch
±±±±±±±±±
Ground
Passenger pretensioner
Driver pretensioner
Ignition switch (power source)±±±±±±±±±
±±±±±±±±±
CONNECTOR ªAº (SDM connector) TERMINAL ARRANGEMENT OF SDM
(VIEWED FROM HARNESS SIDE)
L1
L2Connection detection pin
: Shorting bar
: Air bag harness
ªAº
ªHº : Connector
AIR BAG SYSTEM 10B-5
SYSTEM WIRING DIAGRAM