2003 SUZUKI GRAND VITARA engine control

YH4
GRAND
VITARA
1. 4WD switch
2. Transfer
3. Blank
4. Blank
5. ECM or PCM
6. Glove box7. Air pump assembly
8. Actuator
9. Axle lock clutch
10. Free axle hub
11. 4WD indicator lamp
7E-2 DIFFERENTIAL (FRONT)
4WD CONTROL SYSTEM
When the 4WD switch is turned ON by shifting the transfer shift lever, ECM (PCM) (G16 and J20 engine models)
or 4WD controller (H25 engine model) actuates (energizes) the air pump assembly. Then positive pressure is sent
from the air pump assembly to the actuator installed to the differential case and causes the axle lock clutch and
the free axle hub in the differential case to be engaged, resulting in the 4WD mode. Only when running in the 4WD
mode, front axles are joined to differential case, and they become free when 2WD mode is used (or when transfer
shift lever is shifted to N position), thereby reducing the power loss.

YH4
GRAND
VITARA
7E-6 DIFFERENTIAL (FRONT)
STEPACTIONYESNO
1Turn ON ignition switch (but engine at stop) and
check malfunction indicator lamp.
Does lamp light up?Go to step 2.A trouble has
occurred at some
place. Repair it
referring to
MALFUNCTION
INDICATOR LAMP
(ªCHECK ENGINEº
LAMP) CHECK in
DIAGNOSIS of
SECTION 6.
2Check 4WD switch circuit.
Turn ignition switch ON and check that voltage
between terminal C51-2-18 and terminal C51-3-17
(ground) for G16 / J20 (terminal C51-1-11 and terminal
C51-3-26 (ground) for H25) is as follows.

When transfer shift lever is in N or 2H: 10 ± 14 V

When transfer shift lever is in 4L or 4H: 0 ± 1 V
Is the check result satisfactory?Go to step 3.Check 4WD switch
(refer to SECTION
7A), ªB / Orº and ªBº
circuits of 4WD
switch.
If OK, substitute a
known-good ECM
(PCM) and recheck.
3Check power supply.
1) Turn ignition switch ON.
2) Check voltage between C51-2-7 and C51-3-17
(ground) for G16 / J20 (C51-1-15 and C51-3-26
(ground) for H25). The check results should be as
follows.

When transfer shift lever is in N or 2H: 0 ± 1 V

When transfer shift lever is in 4L or 4H: 10 ± 14 V
Is the check result satisfactory?Go to step 4.Check ªRº circuit. If
it is OK, substitute a
known-good ECM
(PCM) and recheck.
4Check air pump assembly circuit.
1) Check for proper connection to air pump
assembly at all terminals.
2) Turn ignition switch ON.
3) Check voltage between C51-2-27 and C51-3-17
(ground) for G16 / J20 (C51-1-18 and C51-3-26
(ground) for H25). The check result should be as
follows.

When transfer shift lever is in 2H or N: 0 ± 1 V

When transfer shift lever is in 4L or 4H
(more than 4 seconds after shifted to 4L or 4H):
10 ± 14 V
Is the check result satisfactory?Go to step 5.Check air pump
assembly referring
to ªON-VEHICLE
SERVICEº, and then
ªPº circuit.
If OK, substitute a
known-good ECM
(PCM) and recheck.
5Check 4WD indicator lamp circuit.
1) Turn ignition switch ON.
2) Check voltage between E61-19 and C51-3-17
(ground) for G16 / J20 (C51-1-7 and C51-3-26
(ground) for H25). The check result should be as
follows.

When transfer shift lever is in 2H or N: 10 ± 14 V

When transfer shift lever is in 4L or 4H: 0 ± 1 V
Is the check result satisfactory?4WD control system
is in good condition.Check ªOr / Bº circuit
(including indicator
lamp and
combination meter).
If OK, substitute a
known-good ECM
(PCM) and recheck.

YH4
GRAND
VITARA
DIFFERENTIAL (FRONT) 7E-7
1
1. ECM (PCM); viewed from harness side
4WD CONTROL CIRCUIT INSPECTION
Voltage Check [G16 and J20 engine models]
Check for input or output voltage (voltage between each circuit and
body ground) of ECM (PCM) with ECM (PCM) connector con-
nected and ignition switch turned ON.
TER-
MINALCIRCUITWIRE
COLORNORMAL
VOLTAGECONDITION
E6110 ± 14 VTransfer shift lever: 2H or NE61-
194WD Indicator lampOr / B0 ± 1 V4 seconds after transfer shift lever shifted
to 4H or 4L
C51 2Air pump assembly0 ± 1 VTransfer shift lever: 2H or NC51-2
-7(Pump motor and release
valve)R10 ± 14 V1 seconds after transfer shift lever shifted
to 4H or 4L
C51-24WD switchB/Or10 ± 14 VTransfer shift lever: 2H or N
-184WD switchB/Or0 ± 1 VTransfer shift lever: 4H or 4L
C51-
3-17GroundB/Bl0 ± 1 V±
C51 2Airpumpassembly0 ± 1 VTransfer shift lever: 2H or NC51-2
-27
Air um assembly
(pressure switch)P10 ± 14 V4 seconds after transfer shift lever shifted
to 4H or 4L

YH4
GRAND
VITARA
1. To door switch (driver side) B / Bl
2. To transmission range switch G / Bl
(A / T vehicle only, if equipped) L
3. To transmission range switch G / O
(A / T vehicle only, if equipped) 2
4. To transmission range switch Y / G
(A / T vehicle only, if equipped) D
5. To transmission range switch O / Bl
(A / T vehicle only, if equipped) N
6. To transmission range switch O / G
(A / T vehicle only, if equipped) P
7. To transmission range switch R
(A / T vehicle only, if equipped) R
8. To ground B
9. To PCM (A / T vehicle only) W / B
10. To ECT sensor Y / W
11. To fuel level gauge Bl / W
12. To ground B / Y
13. To combination switch G / Y
NOTE:
Terminal arrangement of coupler viewed from harness side.
Coupler A Coupler B Coupler C
Coupler A Coupler B Coupler C
1. Blank ÐÐ
2. Blank ÐÐ
3. To ignition switch B / W
4. Blank ÐÐ
5. To ABS control module Bl / O
(if equipped)
6. To PCM (A / T vehicle only) Gr / Bl
7. To ABS control module Br
(if equipped)
8. To VSS Bl / Y
9. To combination switch G / R
10. To SDM (if equipped) Y / G or Bl
11. To main fuse W / Bl
12. To fuse box W
13. To combination switch R
14. To ECM (PCM for A / T vehicle) V
(if equipped)
15. To ECM (PCM for A / T vehicle) V / Y
16. To ECM (PCM for A / T vehicle) O / B
(if equipped)1. To ground B
2. To ECM (PCM for A / T vehicle) Br
3. To ignition switch (if equipped) V / R
4. To brake fluid level switch R / B
5. To parking brake switch V
6. To seat belt switch (if equipped) Gr / R
7. To generator W / R
8. To oil pressure switch Y / B
9. To combination switch R / Y
10. To ignition switch (if equipped) Bl / R or CHECK
or ENGINE
or ABSif equipped
if equippedif equipped
INSTRUMENTATION / DRIVER INFORMATION 8C-3

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
1. Coil antenna
2. Ignition key
3. Immobilizer control module
4. Data link connector (DLC)
5. Immobilizer diagnostic coupler Ignition key
Transponder
code
Immobilizer
Control
ModuleECM/
PCM
8G-2 IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED)
GENERAL DESCRIPTION
The immobilizer control system designed to prevent vehicle burglar consists of following components.

Engine control module (ECM) / Powertrain control module (PCM)

Immobilizer control module

Ignition key (with built-in transponder)

Coil antenna
Operation of this system is as follows.
(1) Each ignition key has its own code (Transponder code) stored in memory. When the ignition switch is turned
ON, Immobilizer Control Module tries to read the Transponder code through the coil antenna installed to the
steering lock assembly.
(2) Immobilizer Control Module compares the Transponder code read in (1) and that registered in Immobilizer Con-
trol Module and checks if they match.
(3) When it is confirmed that two Transponder codes match each other as described above, Immobilizer Control
Module and ECM / PCM check if ECM/Immobilizer Control Module codes registered in them respectively match.
(4) Only when it is confirmed that ECM/Immobilizer Control Module codes match, the engine starts running. If
Transponder codes in Step (2) or ECM/Immobilizer Control Module codes in Step (3) do not match, ECM / PCM
will stop operation of the injector and ignition of spark plug.

YH4
GRAND
VITARA
0.5TIME (sec.) Ignition switch ON
High Immobilizer
control system
is normal
Immobilizer
control system
is abnormalLow
0.5 0.5 0.5 0.5
High
Low
0.5TIME (sec.) Ignition switch ON
High Immobilizer
control system
is normal
Immobilizer
control system
is abnormalLow
0.5 0.5 0.5 0.5
High
Low
IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED) 8G-5

With the diagnosis switch terminal of monitor coupler for
ECM / PCM not grounded, the ignition switch turned ON (but the en-
gine at stop) and regardless of the condition of the electronic fuel
injection system, ECM / PCM indicates whether a trouble has oc-
curred in the immobilizer control system or not by causing the mal-
function indicator lamp to flash or turn ON.
Malfunction indicator lamp is ON:
No trouble exists in the immobilizer control system.
Malfunction indicator lamp is flashing:
ECM / PCM or Immobilizer Control Module has detected some
trouble in the immobilizer control system.
NOTE:
As soon as the ignition switch is turned ON, ECM / PCM and Im-
mobilizer Control Module diagnose if a trouble has occurred
in the immobilizer control system. While the diagnosis is being
made, the malfunction indicator lamp stays ON and if the diag-
nosis result is ªabnormalº, it immediately changes to flashing
but if the result is ªnormalº, it remains ON. Diagnosis takes
about 3 seconds at maximum.

With the ignition switch turned ON (but the engine at stop) regard-
less of the condition of the electronic fuel injection system,
ECM / PCM indicates whether a trouble has occurred in the immobi-
lizer control system or not by causing the immobilizer indicator lamp
to flash or turn ON.
Immobilizer indicator lamp is ON:
No trouble exists in the immobilizer control system.
Immobilizer indicator lamp is flashing:
ECM / PCM or Immobilizer Control Module has detected some
trouble in the immobilizer control system.
NOTE:
As soon as the ignition switch is turned ON, ECM / PCM and Im-
mobilizer Control Module diagnose if a trouble has occurred
in the immobilizer control system. While the diagnosis is being
made, the Immobilizer indicator lamp stays ON and if the diag-
nosis result is ªabnormalº, it immediately changes to flashing
but if the result is ªnormalº, it remains ON. Diagnosis takes
about 3 seconds at maximum.
When ECM / PCM and Immobilizer Control Module detects a
trouble which has occurred in the above areas, it stores DTC corre-
sponding to the exact trouble area in ECM / PCM and Immobilizer
Control Module memory.
DTCs stored in memory of each controller (Immobilizer Control
Module and ECM / PCM) can be read by using the procedure de-
scribed in ªDIAGNOSTIC TROUBLE CODE CHECK (IMMOBILIZ-
ER CONTROL MODULE)º and ªDIAGNOSTIC TROUBLE CODE
CHECK (ECM / PCM)º in this section.

YH4
GRAND
VITARA
8G-6 IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED)
1. Immobilizer diagnostic coupler
DIAGNOSIS
ECM / PCM and Immobilizer Control Module have on-board diag-
nostic system (a system self-diagnosis function) as described pre-
viously.
Investigate where the trouble is by referring to ªDiagnostic Flow
Tableº and ªDiagnostic Trouble Code Tableº on later pages.
PRECAUTIONS IN DIAGNOSING TROUBLES
[PRECAUTIONS IN IDENTIFYING DIAGNOSTIC TROUBLE CODE]
ECM / PCM


Before identifying diagnostic trouble code indicated by malfunc-
tion indicator lamp, don't disconnect couplers from ECM / PCM,
battery cable from battery, ECM / PCM ground wire harness from
engine.
Such disconnection will clear trouble codes for electronic fuel in-
jection system stored in memory of ECM / PCM.

If abnormality or malfunction lies in two or more areas, malfunc-
tion indicator lamp indicates applicable codes three times each.
And flashing of these codes is repeated as long as diagnosis ter-
minal is grounded and ignition switch is held at ON position.

When ECM / PCM detects a trouble in both electronic fuel injec-
tion system and immobilizer control system, malfunction indicator
lamp indicates trouble codes of both systems alternately while the
ignition switch is turned ON and the diagnosis terminal is
grounded.

Take a note of diagnostic trouble code indicated first.


Before identifying diagnostic trouble code indicated through Su-
zuki scan tool, don't disconnect couplers from ECM / PCM, bat-
tery cable from battery, ECM / PCM ground wire harness from en-
gine.
Such disconnection will clear trouble codes for electronic fuel in-
jection system stored in memory of ECM / PCM.

Take a note of diagnostic trouble code indicated first.
Immobilizer Control Module

Take a note of diagnostic trouble code indicated first.