2008 SUZUKI SWIFT Inspection of ecm and its circuits

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-135
DTC P0616: Starter Relay Circuit LowS7RS0B1104055
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine.
4) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

E23 C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
3
4 7
1
6
RED/WHTGRN/WHT
GRN
RED
BLK/WHT
YEL/GRN
YEL/GRN
WHT
[A]: YEL
[B]: YEL/GRN
25
8
9
10
WHT
WHT/BLUC37-48
E23-30
E23-29
I6RS0C110025-01
[A]: For A/T model
2. Starter motor5. Transmission range switch (for A/T model) 8. “ST SIG” fuse
[B]: For M/T model 3. Ignition switch6. Starting motor control relay 9. “ST MOT” fuse
1. ECM 4. Main fuse box 7. “IG COIL” fuse 10. “IG ACC” fuse
DTC detecting condition Trouble area
Engine starts even though vehicle is at stop and engine
starter signal is low voltage.
(2 driving cycle detection logic) • Engine starter signal circuit
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.

Downloaded from www.Manualslib.com manuals search engine 1A-136 Engine General Information and Diagnosis:
DTC P0617: Starter Relay Circuit HighS7RS0B1104056
Wiring Diagram
Refer to “DTC P0616: Starter Relay Circuit Low”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it at idle for 3 min. or more.
4) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

2 Signal circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure voltage at terminal “C37-48” of ECM connector, under following condition.
Voltage at terminal “C37-48” of ECM connector
While engine cranking: 6 – 14 V
After starting engine: 0 – 1 V
Is each voltage within specified range? Poor “C37-48”
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
If wire and connections
are OK, substitute a
known-good ECM and
recheck.“YEL/GRN” wire is open
or high resistance
circuit.
Step Action Yes No
DTC detecting condition
Trouble area
Engine starter signal is high voltage for 180 seconds
continuously while engine is running.
(2 driving cycle detection logic) • Engine starter signal circuit
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Starter signal check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Start engine, measure voltage between “C37-48” terminal of ECM connector and vehicle body ground.
Is voltage 0 – 1 V? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If OK, substitute a
known-good ECM and
recheck.
Go to Step 3.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-137
DTC P0620: Generator Control CircuitS7RS0B1104057
System and Wiring Diagram
Generator Control System Description
Refer to “Generator Control System Description”.3
Wire circuit check
1) Disconnect starting motor control relay in individual
circuit fuse box No.1 with ignition switch turned OFF.
2) Check for proper connection to starting motor control relay at “RED/WHT”, “RED”, “WHT”, “YEL” (for A/T
model) and “YEL/GRN” (for M/T model) wire terminals.
3) Disconnect connector from starting motor.
4) Measure voltage between “C37-48” terminal of ECM connector and vehicle body ground with ignition switch
turned ON.
Is voltage 0 – 1 V? Go to Step 4. For A/T model, “YEL” or
“YEL/GRN” wire is
shorted to power circuit.
For M/T model, “YEL/
GRN” wire is shorted to
power circuit.
If wires are OK,
substitute a known good
ECM and recheck.
4 Wire circuit check
1) Measure voltage between “RED/WHT” wire terminal of
starting motor control relay connector and vehicle body
ground with ignition switch turned ON.
Is voltage 0 – 1 V? Check starting motor
control relay. If OK,
substitute a known-
good ECM and recheck.
Faulty ignition switch,
check ignition switch
referring to “Ignition
Switch Inspection in
Section 9C”.
If ignition switch is OK,
check for short circuit
between ignition switch
and starting motor
control relay to power
circuit.
Step Action Yes No
IG
L
C
FR
E 4
2
BRN/BLKC37-8
BLU/YELC37-28
B
E23
C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238 1
3 5
I5RS0C110013-01
1. Generator
3. Field coil 5. Ignition switch
2. IC regulator 4. ECM 6. Charge lamp

Downloaded from www.Manualslib.com manuals search engine 1A-138 Engine General Information and Diagnosis:
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool to DLC
2) Turn ON ignition switch and clear DTC.
3) Make sure that all accessory switches are tuned OFF.
4) Start engine and warm it up to normal operating temperature (ECT approx. 90 – 95 °C, 193 – 203 °F).
5) Turn ON the followi ng accessory switches.
• Head light switch.
• Blower motor switch (max position).
• Rear defogger switch.
6) Increase engine speed to 4000 rpm and keep it for 10 sec or more.
7) Decrease engine speed to idle.
8) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
• Battery voltage is higher than specification even through generator control is maximum regulation (duty 100%).
• Battery voltage is lower than specification even through generator control is minimum regulation (duty 0%) and electric
load is less than 15 A.
(1 driving cycle detection logic but MIL does not light up) • Generator and/or its circuit
• Electric load current sensor
•ECM
• Generator drive belt
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Generator drive belt check
1) Check generator drive belt tension referring to “Water
Pump / Generator Drive Belt Tension Inspection and
Adjustment in Section 1J”.
Is check result satisfactory? Go to Step 3.
Adjust or replace
generator drive belt.

Downloaded from www.Manualslib.com manuals search engine 1A-140 Engine General Information and Diagnosis:
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool to DLC.
2) Turn ON ignition switch and clear DTC.
3) Make sure that all accessory switch is tuned OFF.
4) Start engine and warm it up to normal operating temperature (ECT approx. 90 – 95 °C, 193 – 203 °F).
5) Turn ON following accessory switch. • Head lights switch.
• Blower motor switch (max position).
• Rear defogger switch.
6) Increase engine speed to 4000 rpm and keep it for 10 sec. or more.
7) Decrease engine speed to idle.
8) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Generator control circuit check
1) Disconnect connector from generator and ECM with
ignition switch turned OFF.
2) Check for proper connection of wire terminal to generator connector and to ECM connector.
3) If connections are OK, check generator control (generator “C” terminal) circuit and field coil monitor
(generator “FR” terminal) circuit for the following.
• Resistance of each generato r control wire and field
coil monitor wire between generator connector and
ECM connector is less than 1 Ω (continuity check)
• Resistance between generator control wire and field coil monitor wire of generator connector is infinity
(insulation check)
• Resistance between each generator control wire and field coil monitor wire of generator connector and
vehicle body ground is infinity (ground circuit short
check)
• Voltage between each generator control wire and field
coil monitor wire of generator connector and vehicle
body ground is 0 V with ignition switch tuned ON
(power circuit short check)
Are they in good condition? Go to Step 3.
Repair or replace
defective wire.
3 Generator check
1) Check for generator output referring to “Generator Test
(Undercharged Battery Check) in Section 1J” and
“Generator Inspection in Section 1J”.
Is check result satisfactory? Substitute a known
good ECM and recheck.
Repair or replace
generator.

Downloaded from www.Manualslib.com manuals search engine 1A-142 Engine General Information and Diagnosis:
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Electric load current sensor power and ground circuit
check
1) Disconnect connector from electric load current sensor.
2) Check electric load current sensor circuit for the
following.
• Voltage between “BLK/WHT” wire terminal of electric load current sensor conn ector and vehicle body
ground is 10 – 14 V with ignition switch turned ON
• Resistance between “BLK /ORN” wire terminal of
electric load current sensor connector and vehicle
body ground is less than 2 Ω
Are they in good condition? Go to Step 3.
Repair or replace
defective wire.
3 Electric load current sensor output circuit check
1) Disconnect connectors from ECM.
2) Check electric load current sensor circuit for the
following.
• Resistance between “PNK/BLU” wire terminal of electric load current sensor connector and “C37-23”
terminal of ECM connector is less than 2 Ω
• Resistance between “PNK/BLU” wire terminal of electric load current sensor connector and vehicle
body ground is infinity
• Voltage between “PNK/BLU” wire terminal of electric load current sensor conn ector and vehicle body
ground is 0 V with ignition switch turned ON
Are they in good condition? Go to Step 4.
Repair or replace
defective wire.
4 Electric load current sensor check
1) Check for electric load current sensor output referring to
“Electric Load Current Sensor On-Vehicle Inspection in
Section 1C”.
Is check result satisfactory? Substitute a known-
good ECM and recheck.
Faulty electric load
current sensor.

Downloaded from www.Manualslib.com manuals search engine 1A-144 Engine General Information and Diagnosis:
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC P1603: TCM Trouble Code DetectedS7RS0B1104061
Wiring Diagram
DTC Detecting Condition
When ECM receives a trouble code from TCM, which indicates that some problem occurred in sensor circuits and its
calculated values used for operations such as idle speed control, engine power control, and so on by TCM, ECM sets
DTC P1603. (TCM outputs the trouble code to ECM when TCM can not compute the engine control signal due to
malfunctions of sensor circuits used for gear shift control.) Step Action Yes No
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2 Battery voltage supply circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) With engine running, measure voltage between “E23-2” terminal of ECM connector and engine ground.
Is voltage 10 – 14 V? Poor “E23-2”
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
If wire and connections
are OK, substitute a
known-good ECM and
recheck.“RADIO” fuse blown,
“WHT” or “WHT/RED”
wire is circuit open or
short circuit.
E23
C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
1
RED
WHT
C37-13
C37-12
RED
WHTC34-7
C34-17
2
I6RS0C110026-01
1. ECM
2. TCM (for A/T model)

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-145
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC P1674: CAN Communication (Bus Off Error)S7RS0B1104062
Wiring Diagram
ESP ® model
Step Action Yes No
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2 DTC check
1) Check DTC of TCM referring to “DTC Check in Section
5A”.
Is there any DTC(s)? Go to applicable DTC
diag. flow.
Substitute a known-
good ECM and recheck.
[F]
E85
161
15
2
3
4
5
6
7
8
9
10
11
12
13
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
3233
34
35
36
37
38
39
40
41
42
43
44
45
46
47
[D] 12345678910
11
141516
36 34 33 32 31 30 29 24 23
37
181920
G49
[A]
E23
C37
34
1819
567
10
11
17
20
47 46
495051
2122
52 16
25 9
24
14
29
5557 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
4042 39 38
44
45 43 41 331
1213
238
34
1819
567
10
11
17
20
47 46
495051
2122
52 16
25 9
24
14
29
5557 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
4042 39 38
44
45 43 41 331
12
13
238
[C]G28
1234567
8
910
11
1213141516
1718
19
20
212223242526272829303132
[E] G54
109 321
[B]
G37E46
1234567 1234567
8910
11
8910
11
121314 121314
1516171819202122
4
6 1
2
3
REDWHT
REDWHT
REDWHT
REDWHT
REDWHT
E23-3E23-18
E85-42E85-46
E85-13E85-44
E46-1E46-2
G37-4G37-2
REDWHT
REDWHTG49-19G49-18
5
7
WHTG54-9REDG54-10
G28-8G28-10
G28-7REDG28-9WHT
I7RS0B110014-02
[A]: ECM connector (viewed from harness side)
1. ECM
[B]: BCM connector (viewed from harness side) 2. ESP® control module
[C]: Combination meter connector (viewed from harness side) 3. BCM
[D]: Keyless start control module connector (vie wed from harness side) 4. Steering angle sensor
[E]: Steering angle sensor connector (viewed from harness side) 5. Combination meter
[F]: ESP ® control module connector (viewed from terminal side) 6. Keyless start control module
7. CAN junction connector