2000 SUZUKI SWIFT Eps electric module

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-1
6F1
6F2
6G
6H
6K
7A
7A1
3B1
7D
7E
7F
8A
8B
8C
8D
8E
9
10
10A
10B
SECTION 3B1
ELECTRICAL POWER STEERING (P/S) SYSTEM
CONTENTS
GENERAL DESCRIPTION .............................3B1-2
SYSTEM COMPONENTS ........................... 3B1-2
WIRING DIAGRAM ..................................... 3B1-3
DIAGNOSIS ....................................................3B1-4
ON-BOARD DIAGNOSTIC SYSTEM .......... 3B1-4
PRECAUTIONS IN DIAGNOSING
TROUBLES ................................................. 3B1-4
SYSTEM CHECK FLOW TABLE ................ 3B1-5
MALFUNCTION INDICATOR LAMP
(“EPS” WARNING LAMP) CHECK.............. 3B1-7
DTC CHECK ............................................... 3B1-8
DTC CLEARANCE ...................................... 3B1-9
SERIAL DATA LINK CIRCUIT CHECK ..... 3B1-10
DTC TABLE .............................................. 3B1-11
TABLE A - MALFUNCTION INDICATOR
LAMP DOES NOT COME ON AT
IGNITION SWITCH ON BUT LEAVING
ENGINE OFF ............................................ 3B1-13
TABLE B - MALFUNCTION INDICATOR
LAMP FLASHES AT IGNITION SWITCH
ON ............................................................. 3B1-15
TABLE C - MALFUNCTION INDICATOR
LAMP DOES NOT FLASH, JUST
REMAINS ON OR JUST REMAINS OFF
EVEN WITH DIAGNOSIS SWITCH
TERMINAL GROUNDED .......................... 3B1-15
DTC C1111 (DTC No.11) TORQUE
SENSOR MAIN CIRCUIT FAILURE ......... 3B1-16
DTC C1113 (DTC No.13) TORQUE
SENSOR MAIN AND SUB CIRCUIT
FAILURE ................................................... 3B1-16DTC C1115 (DTC No.15) TORQUE
SENSOR SUB CIRCUIT FAILURE........... 3B1-16
DTC C1114 (DTC No.14) TORQUE
SENSOR 5V POWER SUPPLY CIRCUIT
FAILURE ................................................... 3B1-17
DTC C1116 (DTC No.16) TORQUE
SENSOR 8V POWER SUPPLY CIRCUIT
FAILURE ................................................... 3B1-18
DTC C1121/C1123/C1124
(DTC No.21/23/24) VSS CIRCUIT
FAILURE ................................................... 3B1-19
DTC C1122 (DTC No.22) ENGINE
SPEED SIGNAL CIRCUIT FAILURE ........ 3B1-20
DTC C1141/C1142/C1143/C1144/C1145
(DTC No.41/42/43/44/45) MOTOR
CIRCUIT FAILURE ................................... 3B1-21
DTC C1151 (DTC No.51) CLUTCH
CIRCUIT FAILURE ................................... 3B1-22
DTC C1153(DTC No.53) P/S CONTROL
MODULE POWER SUPPLY CIRCUIT
FAILURE ................................................... 3B1-24
DTC C1152/C1154/C1155
(DTC No.52/54/55) P/S CONTROL
MODULE FAILURE .................................. 3B1-24
TROUBLE DIAGNOSIS (FOR TROUBLE
NOT INDICATED BY ON BOARD
DIAGNOSTIC SYSTEM)........................... 3B1-25
INSPECTION OF P/S CONTROL
MODULE AND ITS CIRCUITS ................. 3B1-26
STEERING WHEEL PLAY
INSPECTION ............................................ 3B1-28 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).

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-3
WIRING DIAGRAM
BLK RED
BLK
BLK
BLU
BLK YEL BLU
BLK
YEL
WHT
BRN
PPLBLK/WHT
BLK/RED
PPL/WHTBLK or RED
RED or BLK G24-1-1 G24-2-2
G24-2-1
G24-2-4
G24-2-3
G24-5
G24-3
G24-4
G24-2 G24-1-2
G24-1-3
G24-1-4
G24-1-5
G24-6
G24-8
G24-1 G24-7 12
5
6
124
378
9171611 10
G24-1
G24-3
G24-4
G24-5
G24-6
G24-7G24-8G24-2
13
G24-2-2
G24-2-4 G24-2-3 G24-2-1
14
G24-1-5
G24-1-4 G24-1-3 G24-1-2 G24-1-115
1. Main fuse 7. Monitor coupler (for A/T, ABS, P/S system) 13. Connector “G24”
2. Ignition switch 8. Diagnosis switch terminal (for P/S system) 14. Connector “G24-2”
3.“P/S” fuse (30A) in fuse box 9. Ground terminal 15. Connector “G24-1”
4.“IG METER” fuse (15A) in fuse box 10. P/S control module 16.“EPS” warning lamp
5. ECM 11. Motor and clutch 17. DLC
6. VSS 12. Torque sensor

3B1-4 ELECTRICAL POWER STEERING (P/S) SYSTEM
DIAGNOSIS
The P/S system in this vehicle is controlled by P/S control module. P/S control module has an on-board diagnos-
tic system which detects a malfunction in this system.
When diagnosing troubles, be sure to have full understanding of the outline of “ON-BOARD DIAGNOSTIC SYS-
TEM” and each item in “PRECAUTION IN DIAGNOSING TROUBLE” and execute diagnosis according to “SYS-
TEM CHECK FLOW TABLE”.
ON-BOARD DIAGNOSTIC SYSTEM
P/S control module performs on-board diagnosis (self-diagnosis)
on the system and operates “EPS” warning lamp (1) (malfunction
indicator lamp) as follows.
Malfunction indicator lamp (“EPS” warning lamp) lights when
the ignition switch is turned to ON position (but the engine at
stop) regardless of the condition of P/S control system. This
is only to check the malfunction indicator lamp (“EPS” warn-
ing lamp) bulb and its circuit.
If the areas monitored by P/S control module is free from any
trouble after the engine start (while engine is running), mal-
function indicator lamp (“EPS” warning lamp) turns OFF.
When P/S control module detects a trouble which has
occurred in the areas it monitors, malfunction indicator lamp
(“EPS” warning lamp) turns ON while the engine is running
to warn the driver of such occurrence of trouble and at the
same time it stores the exact trouble area in memory inside
of P/S control module.
PRECAUTIONS IN DIAGNOSING TROUBLES
Take a note of DTC indicated first.
Be sure to read “PRECAUTIONS FOR ELECTRONIC CIRCUIT SERVICE” in Section 0A before inspection
and observe what is written there.
When two or more troubles have occurred, their DTCs are indicated 3 times each starting with the smallest
code number and up.
DTC C1122 (DTC No.22) (engine speed signal failure) is indicated when ignition switch is ON position and
engine is not running but if indication changes to a normal one when engine is started, it means nothing
abnormal.
As DTC is stored in memory of P/S control module, be sure to clear memory after repair by performing the
procedure described in “DTC CLEARANCE”.
1

3B1-6 ELECTRICAL POWER STEERING (P/S) SYSTEM
For identify current DTC, clear history DTC referring to “DTC CLEARANCE” in this section. NOTE:
As execution of “DTC CLEARANCE” will clear all malfunction DTCs, be sure to record all DTCs
before servicing.
When 2 or more codes are indicated, the lowest numbered code will appear first.
If a code not listed on “DTC TABLE” is displayed, then the P/S control module is faulty.
DTC C1122 or DTC No.22 (flashing pattern : 22) is indicated when ignition switch is ON and engine
is not running but if DTC No.12 (flashing pattern : 12) is indicated when engine is started, it means
nothing abnormal.
Current DTC and history DTC can be identified by lighting and flashing of “EPS” warning lamp.
“EPS” warning lamp operates as follow depending on the trouble condition.
Current DTC is set.
(Abnormality exists at
present.)History DTC is set only.
(Faulty condition occurred
once in the past but normal
condition is restored at
present.)Current DTC and history
DTC exist.
“EPS” warning lamp after
engine startedRemains ON. Turn OFF. Remains ON.
“EPS” warning lamp when
shorting diagnosis switch ter-
minal and ground terminalDisplays current DTC. Displays history DTC.Displays current DTC and
history DTC.

3B1-10 ELECTRICAL POWER STEERING (P/S) SYSTEM
SERIAL DATA LINK CIRCUIT CHECK
DIAGNOSTIC FLOW TABLE
CAUTION:
Be sure to perform “SYSTEM CHECK FLOW TABLE” before starting diagnosis according to flow table.
1. Main fuse box 6. Combination meter 11. Data link connector (DLC)
2.“EPS” fuse (30 A) 7. Speedometer 12. To ECM, SDM and ABS hydraulic unit/control module
assembly (if equipped)
3. Ignition switch 8.“EPS” warning lamp 13. P/S control module
4. Circuit fuse box 9. To vehicle speed sensor (VSS) 14. Connector “G24”
5.“IG coil” fuse (15 A) 10. To main fuse box
Step Action Yes No
1Was “SYSTEM CHECK FLOW TABLE” per-
formed?Go to Step 2. Go to “SYSTEM CHECK
FLOW TABLE” in this sec-
tion.
2 1) Make sure that SUZUKI scan tool free from
malfunction and correct cartridge for P/S
system is used.
2) Turn ignition switch to OFF position.
3) Check proper connection of SUZUKI scan
tool to DLC.
Is connection in good condition?Go to Step 3. Properly connect SUZUKI
scan tool to DLC.

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-11
Fig. for Step 4
DTC TABLE
3 1) Check if communication is possible by trying
communication with other controller
(ECM, ABS hydraulic unit/control module
assembly (if equipped) or SDM).
Is it possible to communicate with other control-
ler?Go to Step 4. Repair open in common
section of serial data cir-
cuit (“BLU” wire circuit)
used by all controllers or
short to ground or power
circuit which has occurred
somewhere in serial data
circuit (“BLU” wire circuit).
4 1) With ignition switch is OFF position, discon-
nect 8-pin (“G24”) connector from P/S con-
trol module.
2) Check proper connection at “G24-3” (“BLU”
wire) terminal for serial data circuit.
3) If OK, then check resistance between “G24-
3” (“BLU” wire) terminal and “BLU” wire ter-
minal for serial data circuit in DLC.
Is resistance 1 Ω or less?Substitute a known-good
P/S control module and
recheck.Repair high resistance or
open in “BLU” wire circuit
for P/S system. Step Action Yes No
1. DLC
2.“BLU” wire terminal
CAUTION:
Be sure to perform “SYSTEM CHECK FLOW TABLE” before starting diagnosis according to flow table
of each DTC.
21
3.0
0.3
0.30.3 0.31.0 3.03.0 21 21
Example : When VSS circuit fail (DTC 1121, DTC No.21) is set
“EPS” lightTurn ON
Turn OFF
TIME
(sec.)

3B1-12 ELECTRICAL POWER STEERING (P/S) SYSTEM
DTC (displayed
on SUZUKI scan
tool)“EPS” light flashing pattern
DTC (indicated
by “EPS” light
flashing pattern)Model DIAGNOSTIC ITEM DIAGNOSIS
NO DTC 12 NormalThis code appears
when none of the other
codes are identified.
C1111 11
Torque sensor
Diagnose trouble
according to “DIAG-
NOSTIC FLOW
TABLE” corresponding
to each code No. C1113 13
C1114 14
C1115 15
C1116 16
C1121 21
VSS signal C1123 23
C1124 24
C1122 22Engine speed sig-
nal
C1141 41
Motor C1142 42
C1143 43
C1144 44
C1145 45
C1151 51 Clutch
C1152 52
P/S control module C1154 54
C1155 55
C1153 53P/S control module
power supply

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-13
TABLE A - MALFUNCTION INDICATOR LAMP DOES NOT COME ON AT IGNI-
TION SWITCH ON BUT LEAVING ENGINE OFF
CIRCUIT
1. To main fuse 5.“EPS” warning lamp 9. Ground terminal
2. Ignition switch 6. Combination meter 10. P/S control module
3.“P/S” fuse (30A) in fuse box 7. Monitor coupler 11. Connector “G24”
4.“IG METER” fuse (15A) in fuse box 8. Diagnosis switch terminal
G24-1
G24-8
G24-5
G24-4
G24-2 1
23
4
5 6
7
8
910
BLK/WHT
BLK/WHTBLK/RED
YEL
PPL/WHT
BLKBLK
87 7
6
G24-1
G24-4
G24-5
G24-8G24-2
11