2000 SUZUKI SWIFT service

6-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ON-BOARD DIAGNOSTIC SYSTEM (VEHICLE
WITHOUT IMMOBILIZER INDICATOR LAMP)
ECM diagnosis troubles which may occur in the area including
the following parts when the ignition switch is ON and the engine
is running, and indicates the result by turning on or flashing mal-
function indicator lamp (1).
Heated oxygen sensor (if equipped)
ECT sensor
TP sensor
IAT sensor
MAP sensor
CMP sensor
CKP sensor
Knock sensor (if equipped)
VSS
CPU (Central Processing Unit) of ECM
ECM and malfunction indicator lamp (1) operate as follows.
Malfunction indicator lamp (1) lights when the ignition switch
is turned ON (but the engine at stop) with the diagnosis
switch terminal ungrounded regardless of the condition of
Engine and Emission control system. This is only to check
the malfunction indicator lamp (1) bulb and its circuit.
If the above areas of Engine and Emission control system
are free from any trouble after the engine start (while engine
is running), malfunction indicator lamp (1) turns OFF.
When ECM detects a trouble which has occurred in the
above areas, it makes malfunction indicator lamp (1) turn ON
while the engine is running to warn the driver of such occur-
rence of trouble and at the same time it stores the trouble
area in ECM back-up memory. (The memory is kept as it is
even if the trouble was only temporary and disappeared
immediately. And it is not erased unless the power to ECM is
shut off for specified time below.)
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 (2) is con-
nected to ground terminal (3) with a service wire and ignition
switch is turned ON.)
NOTE:
When a trouble occurs in the above areas and disap-
pears soon while the diagnosis switch terminal is
ungrounded and the engine is running, malfunction
indicator lamp (1) lights and remains ON as long as the
trouble exists but it turns OFF when the normal condi-
tion is restored.
Time required to erase diagnostic trouble code mem-
ory thoroughly varies depending on ambient tempera-
ture as follows.
ODO TRIP AB
1
32

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-11
DATA LINK CONNECTOR (DLC)
ELC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
Serial data line (K line of ISO 9141) is used for SUZUKI scan tool
(Tech-1) to communicate with ECM, TCM, ABS control module
and Air bag SDM.
SUZUKI serial data line is used for SUZUKI scan tool (Tech -1) to
communicate with immobilizer control module.
PRECAUTION IN DIAGNOSING TROUBLE
Do not disconnect couplers from ECM, battery cable from battery, ECM ground wire harness from engine or
main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in ECM memory.
Such disconnection will erase memorized information in ECM memory.
Diagnostic information stored in ECM memory can be cleared as well as checked by using SUZUKI scan
tool (Tech-1) or generic scan tool (Vehicle with immobilizer indicator lamp). Before using scan tool, read its
Operator’s (Instruction) Manual carefully to have good understanding as to what functions are available and
how to use it.
Priorities for diagnosing troubles (Vehicle with immobilizer indicator lamp).
If two or more DTCs are stored, proceed to the flow table of the DTC which has detected earliest in the order
(it can be identified by referring to freeze frame data) 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 (Fuel system too lean/too rich), DTC
P0300/P0301/P0302/P0303/P0304 (Misfire detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172 (Fuel system too lean/too rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304 (Misfire detected)
Be sure to read “Precautions for Electrical Circuit Service” in Section 0A before inspection and observe what
is written there.
ECM Replacement
When substituting a known-good ECM, check for following conditions. Neglecting this check may cause
damage to a known-good ECM.
–Resistance value of all relays, actuators is as specified respectively.
–MAP sensor and TP sensor are in good condition and none of power circuits of these sensors is shorted
to ground.AMBIENT
TEMPERATURETIME TO CUT POWER TO ECM
Over 0°C (32°F) 60 sec. or longer
Under 0°C (32°F) Not specifiable. Select a place with
temperature higher than 0°C (32°F).
2. B+
3. Serial data line (K line of ISO 9141)
4. ECM ground
5. Body ground
6. SUZUKI serial data line
2
3456
1

6-16 ENGINE GENERAL INFORMATION AND DIAGNOSIS
[Without Using SUZUKI Scan Tool] (Vehicle without Immo-
bilizer Indicator Lamp)
1) Check malfunction indicator lamp referring to “Malfunction
Indicator Lamp Check” in this section.
2) With the ignition switch OFF position, disconnect SUZUKI
scan tool if connected and using service wire (4), connect
diagnosis switch terminal (1) to ground terminal (2) in moni-
tor coupler (3).
3) With the ignition switch ON position and leaving engine OFF,
read DTC from flashing pattern of malfunction indicator
lamp. Refer to “Diagnostic Trouble Code Table”.
If lamp remains ON, go to “Diagnostic Flow Table A-4”.
4) After completing the check, turn the ignition switch OFF posi-
tion and disconnect service wire from monitor coupler.
DIAGNOSTIC TROUBLE CODE (DTC) CLEARANCE
Using Scan Tool
1) Connect SUZUKI scan tool (Tech-1) or generic scan tool
(Vehicle with immobilizer indicator lamp) to data link connec-
tor in the same manner as when making this connection for
DTC check.
2) Turn ignition switch ON.
3) Erase DTC and pending DTC according to instructions dis-
played on scan tool. Refer to scan tool operator’s manual for
further details.
4) After completing the clearance, turn ignition switch off and
disconnect scan tool from data link connector. NOTE:
If abnormality or malfunction lies in two or more areas,
malfunction indicator lamp indicates applicable codes
three times each.
And flashing of these codes is repeated as long as
diagnosis terminal is grounded and ignition switch is
held at ON position.
Take a note of diagnostic trouble code indicated first.
2
14
3
NOTE:
DTC and freeze frame data stored in ECM memory are
also cleared in following cases. Be careful not to clear
them before keeping their record.
When power to ECM is cut off (by disconnecting bat-
tery cable, removing fuse or disconnecting ECM con-
nectors)
When the same malfunction (DTC) is not detected
again during 40 engine warm-up cycles. (Vehicle with
immobilizer indicator lamp)

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-47
TABLE A-2 MALFUNCTION INDICATOR LAMP CIRCUIT CHECK - LAMP
REMAINS “ON” AFTER ENGINE STARTS
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to table A-1.
INSPECTION
3 MIL Circuit Check
1) Turn ignition switch OFF and disconnect
connectors from ECM.
2) Check for proper connection to ECM at ter-
minal G02-1 (Case of TYPE A. See NOTE)
or G02-9 (Case of TYPE B. See NOTE).
3) If OK, then using service wire, ground termi-
nal G02-1 (Case of TYPE A. See NOTE) or
G02-9 (Case of TYPE B. See NOTE) in con-
nector disconnected.
Does MIL turn on at ignition switch ON?Substitute a known-good
ECM and recheck.Bulb burned out or “PPL/
YEL” (Case of TYPE A.
See NOTE) or “PPL/
WHT” (Case of TYPE B.
See NOTE) wire circuit
open.
Test switch terminal cir-
cuit grounded (vehicle
without immobilizer indi-
cator lamp) Step Action Yes No
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
Step Action Yes No
1 Diagnostic Trouble Code (DTC) Check
1) Check DTC referring to DTC CHECK
section.
Is there any DTC(s)?Go to Step 2 of ENGINE DIAG.
FLOW TABLE.Go to Step 2.
2DTC Check
1) Start engine and recheck DTC while
engine running.
Is there any DTC(s)?Go to Step 3.
3 MIL Circuit Check
1) Turn OFF ignition switch.
2) Disconnect connectors from ECM.
Does MIL turn ON at ignition switch ON?“PPL/YEL” (Case of TYPE A.
See NOTE) or “PPL/WHT”
(Case of TYPE B. See NOTE)
wire circuit shorted to ground.Substitute a known-good
ECM and recheck.

6-48 ENGINE GENERAL INFORMATION AND DIAGNOSIS
TABLE A-3 MIL CHECK - MIL FLASHES AT IGNITION SWITCH ON (VEHICLE
WITHOUT IMMOBILIZER INDICATOR LAMP)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to TABLE A-1.
INSPECTION
TABLE A-4 MIL CHECK - MIL DOES NOT FLASH OR JUST REMAINS ON EVEN
WITH GROUNDING DIAGNOSIS SWITCH TERMINAL (VEHICLE WITHOUT
IMMOBILIZER INDICATOR LAMP)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to TABLE A-1.
INSPECTION
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
Step Action Yes No
1 MIL Flashing Pattern Check
1) Turn ignition switch ON.
Does lamp flashing pattern indicate diag-
nostic trouble code?Go to Step 2. Substitute a known-good ECM
and recheck.
2 Diag. Switch Circuit Check
Is diag. switch terminal connected to
ground via service wire?System is in good condi-
tion.“PPL/WHT” circuit for monitor
connector shorted to ground. If
circuit is OK substitute a known-
good ECM and recheck.
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
Step Action Yes No
1 MIL Circuit Check
1) Turn ignition switch OFF and disconnect connec-
tors from ECM.
Does MIL turn ON at ignition switch ON?“PPL/YEL” (Case of TYPE A.
See NOTE) or “PPL/WHT”
(Case of TYPE B. See NOTE)
circuit shorted to ground.Go to Step 2.
2 ECM/PCM Connection Check
1) Turn ignition switch OFF.
Is connector (C42-27 (Case of TYPE A. See NOTE)
or C41-14 (Case of TYPE B. See NOTE) connection)
connected to ECM/PCM properly?Go to Step 3. Poor connector connec-
tion.
3 Diag. Switch Terminal Circuit Check
1) Connect connectors to ECM.
2) Using service wire, ground C42-27 (Case of
TYPE A. See NOTE) or C41-14 (Case of TYPE
B. See NOTE) connection) terminal with connec-
tors connected to ECM.
3) Turn ignition switch ON.
Does MIL flash?“PPL/WHT” or “BLK” circuit in
monitor connector is open.Substitute a known-good
ECM and recheck.

6-50 ENGINE GENERAL INFORMATION AND DIAGNOSIS
INSPECTION
Step Action Yes No
1 Main Relay Operating Sound Check
Is operating sound of main relay heard at ignition switch
ON?Go to Step 5. Go to Step 2.
2 Main Relay Check
1) Turn OFF ignition switch and remove main relay (1).
2) Check for proper connection to main relay (1).
3) Check resistance between each two terminals. See Fig.
1 and 2.
Between terminals C and D : Infinity
Between terminals A and B : 56 – 146 Ω
4) Check that there is continuity between terminals C and
D when battery is connected to terminals A and B. See
Fig. 3.
Is main relay in good condition?Go to Step 3. Replace main relay.
3 Fuse Check
Is main fuse in good condition? See Fig. 4.Go to Step 4. Check for short in
circuits connected
to this fuse.
4 ECM Power Circuit Check
1) Turn OFF ignition switch, disconnect connectors from
ECM and install main relay.
2) Check for proper connection to ECM at terminals G02-6
(Case of TYPE A. See NOTE) or C41-11 (Case of TYPE
B. See NOTE), C41-10, C41-5 and C41-6.
3) If OK, then measure voltage between terminal G02-6
(Case of TYPE A. See NOTE) or C41-11 (Case of TYPE
B. See NOTE) and ground, C41-10 and ground with igni-
tion switch ON.
Is each voltage 10 – 14 V?Go to Step 5.“BLK/WHT”, “BLK/
YEL” or “BRN/
WHT” circuit open.
5 ECM Power Circuit Check
1) Using service wire, ground terminal C41-10 and mea-
sure voltage between terminal C41-5 and ground at igni-
tion switch ON.
Is it 10 – 14 V?Check ground cir-
cuits “BRN/WHT”
and “BLK/YEL” for
open.
If OK, then substi-
tute a known-good
ECM and recheck.Go to Step 6.
6 Is operating sound of main relay heard in Step 1? Go to Step 7.“BLK/YEL” or “BLK/
RED” wire open.
7 Main relay check
1) Check main relay according to procedure in Step 2.
Is main relay in good condition?“BLK/YEL” or “BLK/
RED” wire open.Replace main relay.

6-56 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Fig. 1 for Step 2
Fig. 2 for Step 33 Check Wire Harness.
1) Disconnect IAT sensor connector with igni-
tion switch OFF.
2) Check for proper connection to IAT sensor
at “LT GRN/BLK” and “ORN” wire terminals.
3) If OK, then with ignition switch ON, is volt-
age applied to “LT GRN/BLK” wire terminal
about 4 – 6 V? See Fig. 2.Go to Step 5.“LT GRN/BLK” wire open
or shorted to power, or
poor C42-15 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
4 Does scan tool indicate – 40°C (– 40°F) at Step
2.Go to Step 6. Go to Step 5.
5 Check Wire Harness
1) Check intake air temp. displayed on scan
tool with ignition switch ON.
Is – 40°C (– 40°F) indicated?Replace IAT sensor.“LT GRN/BLK” wire
shorted to ground.
If wire is OK, substitute a
known-good ECM and
recheck.
6 Check Wire Harness.
1) Using service wire, connect IAT sensor con-
nector terminals.
2) Check intake air temp. displayed on scan
tool with ignition switch ON. See Fig. 3.
Is 119°C (246°F) indicated?Replace IAT sensor.“LT GRN/BLK” wire open
or poor C42-10 connec-
tion.
If wire and connection are
OK, substitute a known-
good ECM and recheck. Step Action Yes No

6-58 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode no scan tool and check DTC.
INSPECTION
Fig. 1 for Step 2Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check ECT Sensor and its Circuit.
1) Connect scan tool with ignition switch OFF.
2) Turn ignition switch ON.
3) Check engine coolant temp. displayed on
scan tool. See Fig. 1.
Is – 40°C (– 40°F) or 119°C (246°F) indicated?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0 A.
3 Check Wire Harness.
1) Disconnect ECT sensor connector.
2) Check engine coolant temp. displayed on
scan tool.
Is – 40°C (– 40°F) indicated?Replace ECT sensor.“LT GRN” wire shorted to
ground.
If wire is OK, substitute a
known-good ECM and
recheck.
4 Does scan tool indicate – 40°C (– 40°F) at Step
2.Go to Step 6. Go to Step 5.
5 Check Wire Harness.
1) Disconnect ECT sensor connector with igni-
tion switch OFF.
2) Check for proper connection to ECT sensor
at “ORN” and “LT GRN” wire terminals.
If OK, then with ignition switch ON, is voltage
applied to “LT GRN” wire terminal about 4 – 6
V? See Fig. 2.Go to Step 4.“LT GRN” wire open or
shorted to power, or poor
C42-14 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
6 Check Wire Harness.
1) Using service wire, connect ECT sensor
connector terminals. See Fig. 3.
2) Turn ignition switch ON and check engine
coolant temp. displayed on scan tool.
Is 119°C (246°F) indicated?Replace ECT sensor.“ORN” wire open or poor
C42-10 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.