2001 SUZUKI GRAND VITARA ECM

7B1-8 AUTOMATIC TRANSMISSION (4 A/T)
On-Board Diagnostic System (Vehicle with
monitor connector)
For automatic transmission control system, PCM (ECM) has fol-
lowing 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 trouble in electronic shift control sys-
tem, it stores its trouble code in ECM back-up memory. (The
memory is kept as it is even if the trouble was only tempo-
rary and disappeared immediately. And it is not erased
unless the power to PCM is shut off for 30 seconds or
longer.)
•It is possible to communicate through DLC by using not only
SUZUKI scan tool (2) but also generic scan tool. (Diagnostic
information can be accessed by using a scan tool.)
•ECM also indicates trouble area in memory by means of
flashing of malfunction indicator lamp (1) at the time of
inspection. (i.e. when diagnosis switch terminal (3) is con-
nected to ground terminal (4) with a service wire (5) and igni-
tion switch is turned ON.)

AUTOMATIC TRANSMISSION (4 A/T) 7B1-9
Precaution in Diagnosing Trouble
•Don’t disconnect couplers from PCM (ECM), battery cable
from battery, PCM ground wire harness from engine or main
fuse before checking the diagnosis information (DTC, freeze
frame data, etc.) stored in PCM memory. Such disconnec-
tion will clear memorized information in PCM memory.
•Using SUZUKI scan tool or also generic scan tool for vehicle
without monitor connector, the diagnostic information stored
in PCM memory can be checked and cleared as well. Before
its use, be sure to read Operator’s (Instruction) Manual sup-
plied with it carefully to have good understanding of its func-
tions and usage.
•Priorities for diagnosing troubles
If two or more diagnostic trouble codes (DTCs) are stored,
proceed to the flow table of the DTC which was detected
earliest in the order and follow the instruction in that table.
If no instructions are given, troubleshoot diagnostic trouble
codes according to the following priorities.
–Diagnostic trouble codes (DTCs) other than DTC P0171/
P0172/P0174/P0175 (Fuel system too lean/too rich), DTC
P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire
detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too
rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306
(Misfire detected)
•Be sure to read “PRECAUTIONS FOR ELECTRICAL CIR-
CUIT SERVICE” in Section 0A before inspection and
observe what is written there.
•PCM replacement
When substituting a known-good PCM, check for following
conditions.
Neglecting this check may result in damage to a good PCM.
–All relays and actuators have resistance of specified value.
–MAF sensor, MDP sensor, TP sensor and fuel tank pres-
sure sensor are in good condition. Also, the power circuit of
these sensors is not shorted to the ground.

7B1-14 AUTOMATIC TRANSMISSION (4 A/T)
Diagnostic Trouble Code Table
Refer to the same item in Section 6-1.
Fail Safe Table
Refer to the same item in Section 6-1.
Visual Inspection
Visually check following parts and systems.
A/T Basic Check
This inspection is important for troubleshooting when PCM (ECM) has detected no DTC and no abnormality has
been noted in visual inspection. Follow flow table carefully.INSPECTION ITEM REFERRING SECTION
•A/T fluid - - - - - level, leakage, color SECTION 0B
•A/T fluid hoses - - - - - disconnection, looseness, deterioration SECTION 7B1
•Throttle (accelerator) cable - - - - - play, installation SECTION 6E2
•A/T throttle cable - - - - - play, installation SECTION 7B1
•A/T select cable - - - - - installation, operation SECTION 7B1
•Engine oil - - - - - level, leakage SECTION 0B
•Engine coolant - - - - - level, leakage SECTION 0B
•Battery - - - - - fluid level, corrosion of terminal
•Connectors of electric wire harness - - - - - disconnection, friction Section 6-1 or 7B1
•Fuses - - - - - burning SECTION 8
•Parts - - - - - installation, damage
•bolt - - - - - looseness
•Other parts that can be checked visually
•Also check following items at engine start, if possible.
–“O/D OFF” lamp - - - - - Operation SECTION 7B1
–“POWER” lamp - - - - - Operation SECTION 7B1
–Malfunction indicator lamp (“SERVICE ENGINE SOON” lamp) - -
- - - OperationSection 6-1
–Charge warning lamp - - - - - Operation SECTION 6H
–Engine oil pressure warning lamp - - - - - Operation SECTION 8C (SECTION 6A2 for pres-
sure check)
–Engine coolant temp. meter - - - - - Operation
–Other parts that can be checked visually
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE”.
2Perform “MANUAL ROAD TEST” in this section.
Is it OK?Go to Step 3. Go to Step 4.
3Proceed to “TROUBLE DIAGNOSIS TABLE 1” in this
section.
Is trouble identified?Repair or replace
defective parts.Go to Step 5.

7E-2 DIFFERENTIAL (FRONT)
General Description
4WD Control System
System circuit
1. 4WD switch 4. Release valve 7. Front differential 10. To ignition switch
2. Air pump assembly 5. Pressure switch 8. Air hose and pipe 11. ECM or PCM
3. Pump motor 6. Transfer 9. 4WD indicator lamp

7E-4 DIFFERENTIAL (FRONT)
Flow table
Step Action Yes No
1 Turn 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 INDI-
CATOR LAMP
(“CHECK ENGINE”
LAMP) CHECK in
DIAGNOSIS of Sec-
tion 6.
2 Check 4WD switch circuit.
Turn ignition switch ON and check that voltage
between terminal C51-3-7 and terminal C51-3-17
(ground) 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),
“BLK/ORN” and “BLK”
circuits of 4WD switch.
If OK, substitute a
known-good ECM
(PCM) and recheck.
3 Check power supply.
1) Turn ignition switch ON.
2) Check voltage between C51-1-9 and C51-3-17
(ground). 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 “RED” circuit. If
it is OK, substitute a
known-good ECM
(PCM) and recheck.
4 Check air pump assembly circuit.
1) Check for proper connection to air pump assem-
bly at all terminals.
2) Turn ignition switch ON.
3) Check voltage between C51-3-18 and C51-3-17
(ground). 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
“ON-VEHICLE SER-
VICE”, and then
“PNK” circuit.
If OK, substitute a
known-good ECM
(PCM) and recheck.
5 Check 4WD indicator lamp circuit.
1) Turn ignition switch ON.
2) Check voltage between E61-19 and C51-3-17
(ground). 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 “ORN/BLK” cir-
cuit (including indica-
tor lamp and
combination meter).
If OK, substitute a
known-good ECM
(PCM) and recheck.

DIFFERENTIAL (FRONT) 7E-5
4WD Control System Circuit Inspection
Voltage check
Check for input or output voltage (voltage between each circuit and body ground) of ECM (PCM) with ECM
(PCM) connector connected and ignition switch turned ON.
TER-
MINALCIRCUITWIRE
COLORNORMAL
VOLTAGECONDITION
E61-19 4WD Indicator lampORN/
BLK10 –14 V Transfer shift lever : 2H or N
0 – 1 V4 seconds after transfer shift lever shifted
to 4H or 4L
C51-1-9Air pump assembly
(Pump motor and release
valve)RED 0 – 1 V Transfer shift lever : 2H or N
10 – 14 V1 seconds after transfer shift lever shifted
to 4H or 4L
C51-3-7 4WD switchBLK/
ORN10 – 14 V Transfer shift lever : 2H or N
0 – 1 V Transfer shift lever : 4H or 4L
C51-3-17 GroundBLK/
ORN 0 – 1 V –
C51-3-18Air pump assembly
(pressure switch)PNK 0 – 1 V Transfer shift lever : 2H or N
10 – 14 V4 seconds after transfer shift lever shifted
to 4H or 4L
1. ECM (PCM) connector terminal arrangement ; viewed from harness side

INSTRUMENTATION/DRIVER INFORMATION 8C-3
COMBINATION METER INTERNAL CIRCUITS
COMBINATION METER COUPLERS
[A] : Coupler A [B] : Coupler B [C] : Coupler C
1. To Cruise control module (if equipped) GRY/YEL 1. To door switch (drive side) BLK/BLU 1. To ground BLK
2. Blank–2. To transmission range switch
(A/T vehicle only, if equipped) LGRN/BLU 2. To ECM (PCM for A/T vehicle) BRN
3. To ignition switch BLK/WHT 3. To transmission range switch
(A/T vehicle only, if equipped) 2GRN/ORN 3. To ignition switch PPL/RED
4. Blank–4. To transmission range switch
(A/T vehicle only, if equipped) DYEL/GRN 4. To brake fluid level switch RED/BLK
5. To ABS control module (if equipped) BLU/ORN 5. To transmission range switch
(A/T vehicle only, if equipped) NORN/BLU 5. To parking brake switch PPL
6. To PCM (A/T vehicle only) GRY/BLU 6. To transmission range switch
(A/T vehicle only, if equipped) PORN/GRN 6. To seat belt switch GRY/RED
7. To ABS control module (if equipped) BRN 7. To transmission range switch
(A/T vehicle only, if equipped) RRED 7. To generator WHT/RED
8. To VSS BLU/YEL 8. To illumination control module RED/GRN 8. To engine oil pressure switch YEL/BLK
9. To combination switch GRN/RED 9. To PCM (A/T vehicle only) WHT/BLK 9. To combination switch RED/YEL
10. To air bag SDM BLU 10. To ECT sensor YEL/WHT 10. To ignition switch BLU/RED
11. To main fuse WHT/BLU 11. To fuel level gauge BLU/WHT
12. To fuse box WHT 12. To ground BLU/YEL
13. To combination switch RED 13. To combination switch GRN/YEL
14. To immobilizer control module
(if equipped)PPL
15. To ECM (PCM for A/T vehicle) PPL/YEL
16. To ECM (PCM for A/T vehicle) ORN/BLK
P R N D 2 LCRUISEPOWER4WDSPEED
METERTACHO
METERFUEL
METERTEMP.
METER
A-11
A-13 A-8 B-12 B-11 C-8 A-15 A-6 A-1 B-9 A-16 A-14 C-7 C-1 A-10 C-3 C-4 C-5 A-7 A-5 B-8 B-1B-10 C-2 A-12 A-3B-13 B-2 B-3 B-4 B-5 B- B-6 C-9 C-10 A-9ABS circuit EBD circuit Air bag circuit
or ABS or BRAKE
if equipped
or CHECK
ENGINE
NOTE:
Terminal arrangement of coupler viewed from harness side.

CRUISE CONTROL SYSTEM 8E-3
Cruise Control System
The cruise control system is a device which maintains a preset vehicle speed while driving at a high speed, e.g.,
on a highway. It allows the driver to drive his vehicle at a constant speed of 40 km/h (25 mile/h) or higher without
depressing the accelerator pedal (constant cruising). The system also has such functions as to change the vehi-
cle speed without operating the accelerator pedal (but using SET COAST and ACCEL RESUME switches), can-
cel cruise control (CANCEL switch) and resume the speed in memory automatically after cruise control is
cancelled (ACCEL RESUME switch). The system mainly consists of a vehicle speed sensor, an actuator
assembly incorporated with control module, cruise main switch, SET COAST switch, ACCEL RESUME switch
and CANCEL switch, etc.
Cruise control system circuit
Refer to Section 8A.
1. Cruise main switch 6. PCM / ECM
1-1 Cruise main switch indicator lamp 7. Stop lamp switch (with brake pedal position switch)
2.“CRUISE” Indicator light 8. Clutch pedal position switch (M/T vehicle)
3. SET COAST/ACCEL RESUME/CANCEL switch 9. Automatic transmission
4. Vehicle speed sensor 10. Transmission range switch (Park/Neutral position switch) (A/T vehicle)
5. Cruise control actuator assembly (with control module)