2000 SUZUKI SWIFT RG413 Service Workshop Manual

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

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-5
SYSTEM CHECK FLOW TABLE
Step Action Yes No
1 1) Record details of the problem (failure, complaint) and how it
occurred as described by the customer.
For this purpose, use of such a questionnaire from as shown
below will facilitate collecting information to the point required for
proper analysis and diagnosis.
2) Check if what the customer claimed in “CUSTOMER QUES-
TIONNAIRE” is actually found in the vehicle and if that symptom
is found, whether it is identified as a failure.
(This step should be shared with the customer if possible.)
3) Check malfunction indicator lamp (“EPS” warning lamp) opera-
tion referring to “MALFUNCTION INDICATOR LAMP (“EPS”
LIGHT) CHECK”.
4) Check DTC referring to “DTC CHECK” in this section and record
the DTC(s).
5) Clear DTC if any malfunction DTC exists referring to “DTC
CLEARANCE” in this section, then recheck DTC.
Is any malfunction DTC detected?Go to Step 2. Go to Step 3.
2 1) Inspect and repair referring to applicable “DTC TABLE” in this
section.
2) Clear DTC referring to “DTC CLEARANCE” in this section.
Does the trouble recur?Go to Step 5. Go to Step 4.
3 1) Test drive the vehicle and turn steering wheel fully to the right
and left during test driving. See WARNING. Check if any trouble
exists.
2) Inspect and repair basic parts referring to “DIAGNOSIS CHART”
in SECTION 3.
3) If the trouble cannot be repaired in Step 3-2), inspect and repair
referring to “TROUBLE DIAGNOSIS (FOR TROUBLE NOT INDI-
CATED BY ON-BOARD DIAGNOSTIC SYSTEM)” in this sec-
tion.
Does the trouble recur?Go to Step 5. Go to Step 4.
4 1) Confirm that the problem symptom has gone and P/S system is
free from any abnormal conditions. If what has been repaired is
related to the malfunction DTC, clear the DTC once and perform
test driving as in Step 3-1) and confirm that no DTC is indicated.
Is any malfunction DTC detected?Go to Step 5. END
5 1) Check DTC referring to “DTC CHECK” in this section.
Is any malfunction DTC detected?Go to Step 2. Go to Step 3.
WARNING:
Carry out test in very little traffic area to prevent an accident.

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.

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-7
CUSTOMER QUESTIONNAIRE (EXAMPLE)
MALFUNCTION INDICATOR LAMP
(“EPS” WARNING LAMP) CHECK
1) Turn ignition switch to ON position (but without running
engine), check that malfunction indicator lamp (“EPS” warn-
ing lamp) lights up. If lamp does not light up, go to “TABLE
A”. If lamp flashes, go to “TABLE B”.
2) Start engine and check that malfunction indictor lamp
(“CHECK ENGIE” light) turns OFF.
If lamp comes OFF, P/S system is in good condition.

3B1-8 ELECTRICAL POWER STEERING (P/S) SYSTEM
DTC CHECK
USING SUZUKI SCAN TOOL
1) Turn ignition switch to OFF position.
2) After setting cartridge connect SUZUKI scan tool to data link
connector (DLC) (1) located on underside of instrument
panel at driver’s seat side.
Special tool
(A) : 09931-76011
(B) : Master storage cartridge
(C) : 09931-76030
3) Turn ignition switch to ON position.
4) Read DTC according to instructions displayed on SUZUKI
scan tool and print it or write it down referring to SUZUKI
SCAN TOOL OPERATOR’S MANUAL for further details.
5) After completing the check, turn ignition switch to OFF posi-
tion and disconnect SUZUKI scan tool from DLC.
NOT USING SUZUKI SCAN TOOL
1) Remove glove box.
2) Apply chocks to wheels, set shift lever to neutral position and
pull parking brake fully.
3) Start engine.
4) Using jumper wire (4), short diagnosis switch terminal (1) to
ground terminal (2) of monitor coupler (3).
5) Read flashing of “EPS” warning lamp which represents DTC
and write it down. When more than 2 DTCs are stored in
memory, each DTC is repeated 3 times starting with the
smallest DTC number in increasing order.
For details and example of DTC, refer to “DTC TABLE”.
6) After completing the check, turn ignition switch to OFF posi-
tion and disconnect jumper wire (4) from monitor coupler. NOTE:
If Suzuki scan tool cannot display DTC, perform “SERIAL
DATA LINK CIRCUIT CHECK” described in this section.
(B)(A) (C)1
NOTE:
DTC No.22 is indicated when ignition switch is ON and
engine is not running but if DTC No.12 is indicated when
engine is started, it means nothing abnormal.
3
21
3
4

ELECTRICAL POWER STEERING (P/S) SYSTEM 3B1-9
DTC CLEARANCE
USING SUZUKI SCAN TOOL
1) Turn ignition switch to OFF position.
2) After setting cartridge connect SUZUKI scan tool, connect
scan tool to data link connector (DLC) (1) located on under-
side of instrument panel at driver’s seat side.
Special tool
(A) : 09931-76011
(B) : Master storage cartridge
(C) : 09931-76030
3) Turn ignition switch to ON position.
4) Erase DTC according to instructions displayed on SUZUKI
scan tool referring to “SUZUKI SCAN TOOL OPERATOR’S
MANUAL” for further details.
5) After completing the check, turn ignition switch to OFF posi-
tion and disconnect SUZUKI scan tool from DLC.
NOT USING SUZUKI SCAN TOOL
1) Remove glove box.
2) Turn ignition switch to ON position.
3) Using jumper wire, short diagnosis switch terminal (1) to
ground terminal (2) of monitor coupler (3).
4) Make the disconnected end of jumper wire (4) contact where
disconnected (short) and repeat these actions (open and
short) at least 5 times within 10 seconds.
DTC clearance procedure specification
“a” : about 1 second
“b” : within 10 seconds
5) Perform “DTC CHECK” and confirm that normal DTC (DTC
No.12) is displayed and not malfunction DTC.
(B)(A) (C)1
21
3
3
4
“a”
“b”
Open
GroundCondition between diagnosis switch
terminal and ground terminal

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.)