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Electronic Control System Location
NOTE
The figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are installed
at the opposite side.
1
2
3 * 4 *
5
6 *
7 *
8 *
9 *
10 *
21
11
12 13
14
15161718
19
20
I5RS0C722001-01
1. ECT sensor
7. Blower motor13. AUTO switch19. MODE (air flow) selector
2. Outside air temperature sensor 8. Blower motor controller 14. Temperature selector 20. Blower speed selector
3. Sunload sensor 9. Temperature control actuator15. OFF switch21. HVAC control module
4. Air flow control actuator 10. Inside air temperature sensor 16. Air intake selector
5. Evaporator temperature sensor 11. Defroster switch 17. A/C switch
6. Air intake actuator 12. Display 18. Rear defogger switch
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Diagnostic Information and Procedures
A/C System Symptom DiagnosisS7RS0B7224001
4. Rear defogger relay 15. Evaporator temperature sensor 26. Radiator cooling fan relay No.1 37. Rear defogger switch
5. Rear defogger 16. Sunload sensor 27. Radiator cooling fan relay No.2 38. To BCM
6. Blower motor relay 17. Junction block assembly 28. Radiator cooling fan relay No.3 39. To ECM
7. Blower motor 18. ECM 29. Information display 40. To main relay
8. Blower motor controller 19. ECT sensor 30. Lighting switch 41. To main fuse
9. DLC 20. Radiator cooling fan motor 31. A/C switch 42. Back-light
10. Air intake actuator 21. Compressor relay 32. MODE (air flow) selector 43. Defroster indicator 11. Air flow control actuator 22. Compressor 33. Air intake selector 44. Rear defogger indicator
Condition Possible cause Correction / Reference Item
No cool air comes out (A/
C system does not
operate) No refrigerant
Perform recovery, evacuation and charge
referring to “Operation Procedure for
Refrigerant Charge”.
Fuse blown Check related fuses, and then check for short
circuit to ground.
A/C switch faulty Check A/C switch referring to “Inspection of
HVAC Control Module and Its Circuit”.
Evaporator temperature sensor faulty Check evaporator temperature sensor
referring to “Evaporator Thermistor
(Evaporator Temperature Sensor) Inspection”.
A/C refrigerant pressure sensor faulty Check A/C refrigerant pressure sensor
referring to “A/C Refrigerant Pressure Sensor
and Its Circuit Inspection”.
Wiring or grounding faulty Repair as necessary.
ECT sensor faulty Check ECT sensor referring to “ECT Sensor
Inspection in Section 1C”.
ECM faulty Check ECM referring to “A/C System
Inspection at ECM”.
HVAC control module faulty Check HVAC control module referring to
“Inspection of HVAC Control Module and Its
Circuit”.
Magnet clutch faulty Check magnet clutch. Referring to “Magnet
Clutch Inspection”.
Compressor drive belt loosened or
broken Adjust or replace drive belt.
Compressor faulty Check compressor.
Compressor relay faulty Check compressor relay referring to
“Compressor Relay Inspection”.
Temperature selector, blower speed
selector, and/or air flow selector faulty Check HVAC control module referring to
“Inspection of HVAC Control Module and Its
Circuit”.
BCM faulty Check BCM referring to “Inspection of BCM
and its Circuits in Section 10B”.
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Abnormal Noise Symptom Diagnosis of A/C
System
S7RS0B7224002
Refer to “Abnormal Noise Symptom Diagnosis of A/C
System”.
DTC CheckS7RS0B7224003
Using SUZUKI Scan Tool1) Turn ignition switch to OFF position.
2) Connect SUZUKI scan tool to data link connector (DLC) (1) located on underside of instrument panel
at driver’s seat side.
Special tool
(A): SUZUKI scan tool 3) Light over sunload sensor vertically with an
incandescent lamp of approximately 100 W apart
from about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent lamp, DTC B1504 is detected
even though there is not any malfunction.
4) Turn ignition switch to ON position.
5) Read DTC displayed on SUZUKI scan tool.
NOTE
To know how to use SUZUKI scan tool, refer
to operator’s manual for SUZUKI scan tool.
6) After completing the check, turn ignition switch to
OFF position and disconnect SUZUKI scan tool from
data link connector (DLC).
Cool air does not come
out only at high speed
Excessive amount of refrigerant
Check the amount of refrigerant.
A/C evaporator frosted Check A/C evaporator and evaporator
temperature sensor referring to “Evaporator
Inspection” and “Evaporator Thermistor
(Evaporator Temperature Sensor) Inspection”.
Insufficient air flow of
cooled air A/C evaporator clogged or frosted
Check A/C evaporator and evaporator
temperature sensor referring to “Evaporator
Inspection” and “Evaporator Thermistor
(Evaporator Temperature Sensor) Inspection”.
Air leaking from HVAC unit or air duct Repair as necessary.
Blower motor faulty Check blower motor referring to “Blower Motor
Inspection in Section 7A”.
Wiring or grounding faulty Repair as necessary.
Condition Possible cause Correction / Reference Item
(A)
1
I5RS0A722005-01
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Not Using SUZUKI Scan Tool
Current DTC mode1) Light over sunload sensor vertically with an incandescent lamp of approximately 100 W apart
from about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent lamp, DTC B1504 is detected
as current DTC even though there is not any
malfunction.
2) Start engine.
3) Wait for 20 seconds or more after engine started and set temperature selector to 25 °C (77 °F).
4) Push AUTO switch (1) and defroster switch (2) at the same time.
5) Check DTC (3).
NOTE
• DTC flashes for 15 seconds. After that, the normal display is rest ored. To have DTC
displayed again, repeat the procedure from
Step 4.
• When more than two DTCs are detected, only DTC having the highest priority is
indicated. Therefore, after troubleshooting
the malfunction, DTC check has to be
performed again to see if any other DTC(s)
is detected.
History DTC mode
1) Turn ignition switch to ON position.
2) Set temperature selector to 25 °C (77 °F).
3) Push AUTO switch (1) and MODE (air flow) selector
(2) at the same time.
4) Check DTC (4).
NOTE
Each DTC item is displayed (lights up) for 4
seconds.
When HVAC control module detects 2 or
more DTC items, each one is displayed once
starting from the one of higher priority order.
After all DTC items being detected have been
displayed, “Ed” (3) appears on display of
HVAC control module and normal display is
restored. “Ed” means that all DTC items have
been displayed.
DTC ClearanceS7RS0B7224004
NOTE
Only history DTC(s) can be cleared. Current
DTC(s) can not be cleared unless the
problem(s) is fixed.
Using SUZUKI Scan tool
1) Turn ignition switch to OFF position.
2) Connect SUZUKI scan tool to data link connector (DLC) (1) located on underside of instrument panel
at driver’s seat side.
Special tool
(A): SUZUKI scan tool1
2
3
I5RS0A722006-02
1
2 34
I5RS0A722007-02
(A)
1
I5RS0A722005-01
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3) Light over sunload sensor vertically with an incandescent lamp approximately 100 W apart from
about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent lamp, DTC B1504 is detected
as current DTC even though there is not any
malfunction.
4) Turn ignition switch to ON position.
5) Erase DTC according to instructions displayed on SUZUKI scan tool.
NOTE
To know how to use SUZUKI scan tool, refer
to operator’s manual for SUZUKI scan tool.
6) After completing the clearance, turn ignition switch to OFF position, and then di sconnect SUZUKI scan
tool from DLC.
Not Using SUZUKI Scan Tool 1) Turn ignition switch to ON position.
2) Set temperature selector to 25 °C (77 °F). 3) Push AUTO switch (1) and
MODE (air flow) selector
(2) at the same time to have history DTC displayed.
4) Push MODE (air flow) selector (2) and OFF switch (3) at the same time while history DTC is displayed.
5) Check that “CL” (4) appears on display. “CL” means that DTC has been cleared.
DTC TableS7RS0B7224005
CAUTION!
Be sure to perform “Air Conditioning Sy stem Check” before starting diagnosis.
1
2
3
2
4
I5RS0A722008-01
DTC No.
(displayed on
SUZUKI
scan tool) DTC
(indicated on
display of HVAC
control
module) Priority of
display
(current DTC) Priority
of
display
(history DTC) Diagnosis
“AUTO”
indicator lamp
) B1502 21 1 1 Inside air temperature sensor and/or its
circuit malfunction Open
Flashed
22 2 2 Short
) B1503 31 3 3 Evaporator temperature sensor and/or its
circuit malfunction Open
Flashed
32 4 4 Short
) B1504 41 21 — Sunload sensor and/or its circuit
malfunction Open —
42 5 5 Short Flashed
) B1511 61 6 6 Temperature control actuator (position
sensor) and/or its circuit malfunction Open
Flashed
62 7 7 Short
) B1512 71 8 8 Air flow control actuator (position sensor)
and/or its circuit malfunction Open
Flashed
72 9 9 Short
) B1513 63 10 10 Temperature control actuator and/or its circuit malfunction Flashed
) B1514 73 11 11 Air flow control actuator and/or its circuit malfunction Flashed
) B1541 E1 12 — HVAC control module back-up power supply malfunction —
) B1546 d5 22 — A/C refrigerant pressure malfunction —
) B1551 91 13 12
Serial communication circuit malfunction Open
Flashed
92 14 13 Short
) B1552 94 15 14 Serial communication signal malfunction Flashed
) B1553 A4 16 15 CAN communication signal malfunction Flashed
) B1557 b4 19 16 Vehicle speed sensor signal malfunction —
) B1561 54 17 17 Engine coolant temperature sensor signal malfunction Flashed
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NOTE
When no current DTC is detected, all contents displayed on display (1) of HVAC control module and
defroster indicator (2) flash at the same time.
Fail-Safe TableS7RS0B7224006
When any of the following malfunctions (DTCs) is detected, fail-safe mode is activated.
However, when HVAC control module detects normal ope ration of A/C system, fail-safe mode is cancelled.
)
B1562 14 18 18 Outside air temperatur e sensor signal malfunction Flashed
) B1563 d4 20 19 A/C refrigerant pressure sensor signal malfunction —
— See NOTE
below
(current DTC) ——Normal —
00 (history DTC)
DTC No.
(displayed on
SUZUKI
scan tool) DTC
(indicated on
display of HVAC
control
module) Priority of
display
(current DTC) Priority
of
display
(history DTC) Diagnosis
“AUTO”
indicator lamp
1
2
I5RS0A722009-01
DTC No.
Trouble Area Fail-Safe Operation
)
B1502 Inside air temperature sensor and/
or its circuit HVAC control module controls actu
ators assuming that inside air
temperature is 25 ° C (77 °F).
)
B1503 A/C evaporator temperature sensor
and its circuit • HVAC control module turn
s off A/C switch signal.
• HVAC control module controls actu ators assuming that evaporator
temperature is 0 ° C (32 °F).
)
B1504 Sunload sensor and/or its circuit HVAC control module controls actu
ators assuming that amount of
sunlight is 0 W/m
2.
) B1551 Serial communication circuit
HVAC control module controls actuators assuming that outside air
temperature is 20 ° C (68 °F), engine coolant temperature is 80 °C
(176 °F), and vehicle speed is 40 km/h (25 mph).
)
B1552 Serial communication circuit
)
B1553 CAN communication circuit
)
B1557 Vehicle speed sensor and/or its
circuit HVAC control module controls act
uators assuming that vehicle speed
is 40 km/h (25 mph).
)
B1561 Engine coolant temperature sensor
and/or its circuit HVAC control module controls act
uators assuming that engine coolant
temperature is 80 ° C (176 °F).
)
B1562 Outside air temperature sensor
and/or its circuit HVAC control module controls actu
ators assuming that outside air
temperature is 20 ° C (68 °F).
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DTC B1546: A/C Refrigerant Pressure MalfunctionS7RS0B7224018
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1551: Serial Communication Circuit MalfunctionS7RS0B7224019
Wiring DiagramDTC detecting condition Trouble area
A/C refrigerant pressure sensor signal voltage is lower t han specified value
even though outside air temperature is higher than specified value for
specified time continuously. • Insufficient of refrigerant
• A/C refrigerant pressure sensor
• Outside air temperature sensor
• HVAC control module
Step
Action YesNo
1 A/C refrigerant pressure and outside air temperature
check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Start engine and select “DATA LIST” mode on scan tool.
3) Check “Refrigerant Pressure” and “Outside Air Temp” varies displayed on scan tool.
Is displayed each va ries described varies in “Scan Tool
Data”? Go to Step 2.
Check the amount of
refrigerant and system
for leaks.
2 A/C system performance check
1) Check A/C system performance referring to “A/C System
Performance Inspection”.
Is check result satisfactory? Go to Step 3.
Repair or replace
defective part.
3 A/C refrigerant pressure sensor check
1) Check A/C refrigerant pressure sensor referring to “A/C
Refrigerant Pressure Sensor and Its Circuit Inspection”.
Is check result satisfactory? Go to Step 4.
A/C refrigerant pressure
sensor faulty.
4 Outside air temperature sensor check
1) Check outside air temperature sensor referring to
“Information Display (Clock) Removal and Installation in
Section 9C”.
Is check result satisfactory? HVAC control module
faulty.
Outside air temperature
sensor faulty.
YEL17812910
65 431516 14 13 12 11
G52
789101920121112
65 431718 16 15 14 13
G51
G51-7
12V
2
3
G37-11
I5RS0A722016-01
1. HVAC control module 2. BCM3. Information display
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DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1552: Serial Communication Signal MalfunctionS7RS0B7224020
DTC Detecting Condition and Trouble AreaDTC detecting condition Trouble area
Serial communication signal is higher than or lower than specified value for
specified time continuously. • Serial communication line of BCM
• BCM (included in junction block
assembly)
• Information display
• HVAC control module
Step Action YesNo
1 DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Disconnect connector from information display.
3) Turn ignition switch ON and check DTC.
Is there DTC B1551? Go to Step 2.
Information display
faulty.
2 Wire harness check
1) Disconnect connectors from BCM and HVAC control
module.
2) Measure resistance between “G37-11” terminal of BCM connector and “G51-7” terminal of HVAC control module
connector.
Is resistance below 5
Ω? Go to Step 3. “YEL” wire open or high
resistance circuit.
3 Wire harness check
1) Measure resistance between “G51-7” terminal of HVAC
control module connector and vehicle body ground.
Is resistance infinity? Go to Step 4. “YEL” wire shorted to
ground circuit.
4 Wire harness check
1) Measure voltage between “G51-7” terminal of HVAC
control module connector and vehicle body ground with
ignition switch turned ON.
Is voltage 0 V? Go to Step 5. “YEL” wire shorted to
other circuit.
5 Serial communication signal check
1) Connect connectors to BCM and HVAC control module.
2) Using oscilloscope, check that serial communication
signal is outputted referring to “Reference waveform
No.8” of “Inspection of BCM and its Circuits in Section
10B”.
Is serial communication signal outputted at “G37-11”
terminal of BCM connector? HVAC control module
faulty.
BCM (included in
junction block
assembly) faulty.
DTC detecting condition
Trouble area
Data received by HVAC control module from BCM is erroneous continuously. • BCM (included in junction block assembly)
• HVAC control module