2000 SUZUKI SWIFT check engine

8G-2 IMMOBILIZER CONTROL SYSTEM
PROCEDURE AFTER IMMOBILIZER CONTROL
MODULE REPLACEMENT ........................... 8G-24
PROCEDURE AFTER ECM
REPLACEMENT............................................ 8G-25SPECIAL TOOL ............................................ 8G-25

GENERAL DESCRIPTION
The immobilizer control system designed to prevent vehicle burglar consists of following components.
Engine control module (ECM)
Immobilizer control module (1) with coil antenna
Ignition key (2) with built-in transponder
Operation of this system is as follows.
i) 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.
ii) Immobilizer Control Module compares the Transponder code read in Step (i) and that registered in Immo-
bilizer Control Module and checks if they match.
iii) When it is confirmed that two Transponder codes match each other as described above, Immobilizer Con-
trol Module and ECM check if ECM/Immobilizer Control Module codes registered in them respectively
match.
iv) Only when it is confirmed that ECM/Immobilizer Control Module codes match, the engine starts running. If
Transponder codes in Step (ii) or ECM/Immobilizer Control Module codes in Step (iii) do not match, ECM
will stop operation of the injector and ignition of spark plug.
3. Data link connector (DLC)
4. Immobilizer indicator lamp
5. ECM

8G-4 IMMOBILIZER CONTROL SYSTEM
ON-BOARD DIAGNOSTIC SYSTEM
(SELF-DIAGNOSIS FUNCTION)
Immobilizer Control Module and ECM diagnose troubles which
may occur in the area including the following parts when the igni-
tion switch is ON.
ECM :
ECM/Immobilizer Control Module code
Serial data link circuit
ECM
Immobilizer Control Module :
Transponder code
Coil antenna
ECM/Immobilizer Control Module code
Serial data link circuit
Immobilizer Control Module
Ignition signal
With the ignition switch turned ON (but the engine at stop) regard-
less of the condition of the engine and emission control system,
ECM indicates whether a trouble has occurred in the immobilizer
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 or Immobilizer Control Module has detected some trouble in
the immobilizer control system.
When ECM and Immobilizer Control Module detects a trouble, it
stores DTC corresponding to the exact trouble area in ECM and
Immobilizer Control Module memory.
DTCs stored in memory of each controller (Immobilizer Control
Module and ECM) can be read by using the procedure described
in “DIAGNOSTIC TROUBLE CODE CHECK (IMMOBILIZER
CONTROL MODULE)” and “DIAGNOSTIC TROUBLE CODE
CHECK(ECM)” in this section. NOTE:
As soon as the ignition switch is turned ON, ECM and
Immobilizer 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 diagnosis result is “abnormal”, it
immediately changes to flashing but if the result is “nor-
mal”, it remains ON. Diagnosis takes about 3 seconds at
maximum.

IMMOBILIZER CONTROL SYSTEM 8G-5
DIAGNOSIS
PRECAUTIONS IN DIAGNOSING TROUBLES
PRECAUTIONS IN IDENTIFYING DIAGNOSTIC TROUBLE CODE
ECM
Before identifying diagnostic trouble code indicated through Suzuki scan tool, don't disconnect couplers from
ECM, battery cable from battery, ECM ground wire harness from engine.
Such disconnection will clear trouble codes for engine and emission control system and immobilizer control
system stored in memory of ECM.
Take a note of diagnostic trouble code indicated first.
IMMOBILIZER CONTROL MODULE
Take a note of diagnostic trouble code indicated first.
INTERMITTENT TROUBLES
There is case where Suzuki scan tool indicate a diagnostic trouble code representing a trouble which
occurred only temporarily and has gone. In such case, it may occur that good parts are replaced unneces-
sarily. To prevent such accident, be sure to follow instructions given below when checking by using “Diag-
nostic Flow Table”.
–When trouble can be identified, it is not an intermittent one :
Check coil antenna, ignition key, wires and each connection and if they are all in good condition, substi-
tute a known-good ECM and recheck.
–When trouble can not be identified but Suzuki scan tool indicate a trouble code :
Diagnose trouble by using that code No. and if ignition key, coil antenna, wires and each connection are
all in good condition, turn OFF ignition switch and then ON.
Then check what Suzuki scan tool indicate.Only when they indicate trouble code again, substitute a known-
good ECM or Immobilizer Control Module and check again.
If they indicate not trouble code but normal code, it means that an intermittent trouble did occur and has gone. In
this case, check wires and connections carefully again.

8G-6 IMMOBILIZER CONTROL SYSTEM
DIAGNOSTIC FLOW TABLE
Fig. 1 for Step 1Step Action Yes No
1 1) Check immobilizer indicator lamp while igni-
tion switch is ON (but without starting
engine). See Fig. 1.
Does immobilizer indicator lamp flash?Go to Step 3. If immobilizer indicator lamp
remains ON, go to Step 2.
If immobilizer indicator lamp
remains OFF, go to “TABLE
A IMMOBILIZER INDICA-
TOR LAMP CHECK” in this
section.
2 1) Check DTC stored in ECM referring to
“DIAGNOSTIC TROUBLE CODE CHECK
(ECM)” in this section.
Is there any DTC(s)?Go to “TABLE B
IMMOBILIZER INDI-
CATOR LAMP
CHECK” in this sec-
tion.Immobilizer control system is
in good condition.
3 1) Check DTC stored in immobilizer control
module referring to “DIAGNOSTIC TROU-
BLE CODE CHECK (IMMOBILIZER CON-
TROL MODULE)” in this section.
Is there any DTC(s)?Go to flow table for
DTC No.Go to Step 4.
4 1) Check DTC stored in ECM referring to
“DIAGNOSTIC TROUBLE CODE CHECK
(ECM)” in this section.
Is there any DTC(s) for immobilizer control sys-
tem?Go to flow table for
DTC No.Substitute a known-good
ECM and recheck.
See NOTE below.
NOTE:
After replacing with a known-good ECM, register ECM/Immobilizer Control Module code in ECM by
performing procedure described in “Procedure after ECM Replacement” section.

8G-8 IMMOBILIZER CONTROL SYSTEM
DIAGNOSTIC TROUBLE CODE (DTC) CHECK
(ECM)
1) Turn ignition switch OFF.
2) After setting cartridge to Suzuki scan tool, connect it to data
link connector (DLC) (1) located on underside of instrument
panel at driver’s seat side.
Special tool
(A) : 09931-76011 (Suzuki scan tool)
(B) : Mass storage cartridge
(C) : 09931-76030 (16/14 pin DLC cable)
3) Turn ignition switch ON.
4) Read DTC stored in ECM according to instructions displayed
on Suzuki scan tool and print it or write it down. Refer to
Suzuki scan tool operator’s manual for further details.
If communication between Suzuki scan tool and ECM is not
possible, check if Suzuki scan tool is communicable by con-
necting it to ECM in another vehicle. If communication is
possible in this case, Suzuki scan tool is in good condition.
Then check data link connector and serial data line (circuit)
in the vehicle with which communication was not possible.
5) After completing the check, turn ignition switch OFF and dis-
connect Suzuki scan tool from data link connector (DLC). NOTE:
When reading DTC stored in ECM using Suzuki scan
tool, select “ECM” from the applications menu and
“SUZUKI mode” from the communication mode menu
displayed on Suzuki scan tool.
If ECM detects a trouble in both engine and emission
control system and immobilizer control system, Suzuki
scan tool indicates trouble codes of both systems
using Suzuki mode of ECM application.
1
(C)(A)
(B)

IMMOBILIZER CONTROL SYSTEM 8G-11
TABLE B - IMMOBILIZER INDICATOR LAMP CHECK (IMMOBILIZER INDICA-
TOR LAMP REMAINS ON AFTER ENGINE STARTS)
WIRING DIAGRAM
INSPECTION
1. Main fuse 2. Main relay 3. ECM 4. Immobilizer indicator lamp
BRN/WHT
BLK/RED
BLK/WHT
PNKBLK
BLK/ORG
BLK/ORG
BLK/YEL
C42-2
C42-1
C42-3 C41-10
C41-5/6
G02-6
G02-12
4
1
2
3
Step Action Yes No
1 1) With ignition switch OFF, disconnect cou-
plers from ECM.
Does immobilizer indicator lamp turn ON at
ignition switch ON?“PNK” wire shorted to
ground circuit.Substitute a known-good
ECM and recheck.

8G-20 IMMOBILIZER CONTROL SYSTEM
INSPECTION OF ECM, IMMOBILIZER CON-
TROL MODULE AND ITS CIRCUIT
ECM, Immobilizer Control Module and its circuit can be checked
at ECM wiring couplers and Immobilizer Control Module wiring
coupler by measuring voltage. Described here is only inspection
of Immobilizer Control Module. For inspection of ECM, refer to
“ENGINE & EMISSION CONTROL INPUT/OUTPUT TABLE” in
Section 6E1.
Voltage Check
1) Remove Immobilizer Control Module from steering lock
assembly with ignition switch OFF, referring to “REMOVAL”
of “IMMOBILIZER CONTROL MODULE” in this section.
2) Connect Immobilizer Control Module coupler to Immobilizer
Control Module.
3) Check voltage at each terminal of coupler connected.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.
NOTE:
As each terminal voltage is affected by the battery volt-
age, confirm that it is 11V or more when ignition switch is
ON.
1. Immobilizer Control Module
2. Immobilizer Control Module coupler
3. Body ground
TERMINAL CIRCUIT NOMAL VOLTAGE CONDITION
G06-1 Ground––
G06-2Data link connector
(Serial data terminal)4 – 5V Ignition switch ON
G06-3 Ignition signal10 – 14V Ignition switch ON
0 – 0.8V Ignition switch OFF
G06-4 Power source 10 – 14V Ignition switch ON

AIR BAG SYSTEM 10B-21
TABLE E - SDM CANNOT COMMUNICATE THROUGH THE SERIAL DATA CIR-
CUIT
WIRING DIAGRAM
TABLE TEST DESCRIPTION
STEP 1 : An improper connection to the data link connector (DLC) will prevent communications from being
established.
STEP 2 : This test checks whether it is possible to communicate with other control module.
STEP 3 : This test checks for an open in “BLU” circuit (in air bag harness).
DIAGNOSTIC FLOW TABLE
[A]: Air bag harness 5.“AIR BAG” fuse 10.“AIR BAG” monitor coupler
1. From main fuse 6. Connection detection pin 11. Ground for air bag system
2. Ignition switch 7. SDM 12. Ground on body
3.“IG METER” fuse 8. DLC 13. Ground on Engine block
4.“AIR BAG” warning lamp in combination lamp 9. To ECM, TCM (if equipped) and ABS con-
trol module (if equipped)14. Immobilizer control module (if equipped)
1
14
12
34 BLK/YEL
BLK/YEL
YELBLK/WHT
BLK
BLU/ORNYEL/BLKYEL/BLK
6
RED
WHT/REDRED
BLU
BLU
BLU
5
9
10
11
PPL
BLK
“Q04”“Q06”
Q06-2
Q06-4
Q06-14
Q06-15
Q06-17L1
L2
IG
SDL
DNS
GNDLA
7
[A]
12V
5V
“G39”“Q02”
812
13
CAUTION:
Be sure to perform AIR BAG DIAGNOSTIC SYSTEM CHECK before starting diagnosis according to
flow table.
When measurement of resistance or voltage is required in this table, use a tester along with a cor-
rect terminal adapter from special tool (Connector test adapter kit).
When a check for proper connection is required, refer to INTERMITTENT AND POOR CONNEC-
TIONS in this section.
If there is open circuit in the air bag wire harness, connector or terminal is found damaged, replace
the wire harness, connector and terminal as an assembly.
Step Action Yes No
1 1) Make sure that SUZUKI scan tool is free from malfunc-
tion and correct cartridge for air bag system is used.
2) Ignition switch OFF.
3) Check proper connection of SUZUKI scan tool to DLC.
Is connection in good condition?Go to step 2. Properly connect SUZUKI
scan tool to DLC.