2006 SUZUKI SX4 5C 1

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-53
) B1521Blower Speed
Selector
Malfunction16 1Signal voltage of blower speed selector in HVAC
control module is higher than specification.Flashed
16 2Signal voltage of blower speed selector in HVAC
control module is lower than specification.Flashed
) B1522Air Flow Selector
Malfunction17 1Signal voltage of airflow selector in HVAC control
module is higher than specification.Flashed
17 2Signal voltage of airflow selector in HVAC control
module is lower than specification.Flashed
) B1541Back-up Power
Supply Circuit
Malfunction14 1• Back-up power supply voltage of HVAC control
module is higher than or lower than
specification.
• When connect battery with vehicle and then,
turn ignition switch to ON position for first time.—
) B1546A/C Refrigerant
Pressure
Malfunction13 5• Signal voltage of outside air temperature sensor
is more than specified value. However, A/C
refrigerant pressure is less than specified value.
• Insufficient refrigerant in A/C system.—
) B1551Serial
Communication
Circuit
Malfunction91Circuit voltage of serial communication circuit is
higher than specification.Flashed
92Circuit voltage of serial communication circuit is
lower than specification.Flashed
) B1552HVAC Control
Module Check
Sum Error94HVAC control module received unspecified data
from BCM more than 8 times.Flashed
) B1553CAN
Communication
Circuit
Malfunction10 4HVAC control module received signal indicating
reception error from ECM.Flashed
) B1557VSS Signal
Failure11 4HVAC control module receives invalid data of VSS
signal from BCM.—
) B1561ECT signal
Failure54HVAC control module receives invalid data of ECT
signal from BCM.Flashed
) B1562Outside
Temperature
Sensor Signal
Failure14HVAC control module receives invalid data of
outside air temperature sensor signal from BCM.Flashed
) B1563A/C Refrigerant
Pressure Sensor
Signal Failure13 4HVAC control module receives invalid data of A/C
refrigerant pressure sensor signal from BCM.—
) B1570Engine Type
Signal Failure20 4HVAC control module receives invalid data of
engine type signal from BCM.—
) B1571Combination
Meter Spec
Signal Failure21 4HVAC control module receives invalid data of
combination meter spec signal from BCM.—
NO CODE Normal See NOTE below — —DTC No.
(displayed
on SUZUKI
scan tool)Detection itemDTC (indicated on
HVAC control
module)
Condition when trouble detected (DTC is
determined when following condition detected)“A/C”
indicator
light Indicated
by “REC”
indicator
lightIndicated
by “FRE”
indicator
light

Downloaded from www.Manualslib.com manuals search engine 7B-54 Air Conditioning System: Automatic Type
DTC of A/C System detected by ECM
NOTE
When no DTC is detected, “FRE” [A] and “REC” [B] indicator lights on HVAC control module flash at
the same time in specific pattern.

Fail-Safe TableS6RW0D7224007
When any of the following malfunctions (DTCs) is detected, fail-safe mode is activated.
However, when HVAC control module detects normal operation of A/C system, fail-safe mode is canceled. DTC No. Detection itemDetecting condition
(DTC will set when detecting)MIL
P0481 Fan 2 Control Circuit
Refer to “Fail-Safe Table in Section 1A”. P0532A/C Refrigerant Pressure
Sensor Circuit Low
P0533A/C Refrigerant Pressure
Sensor Circuit High
H: ON a. About 3 seconds
L: OFF b. About 1 seconds
DTC No. Trouble AreaFail-Safe Operation
When ignition switch is turned ON
after malfunction is already detectedWhen malfunction is detected during
ignition switch is ON
) B1502Inside air temperature
sensor circuitHVAC control module maintains last
normal value.HVAC control module controls actuators
assuming that inside air temperature is
25 °C (77 °F).
) B1503A/C evaporator
temperature sensor
circuitHVAC control module assuming that
evaporator temperature is 0 °C (32 °F).• HVAC control module turns off A/C
switch signal.
• HVAC control module controls
actuators assuming that evaporator
temperature is 0 °C (32 °F).
) B1504 Sunload sensor circuitHVAC control module maintains last
normal value.HVAC control module controls actuators
assuming that amount of sunlight is 0 W/
m
2.
) B1520Temperature selector
malfunctionHVAC control module maintains last
normal value.HVAC control module controls actuators
assuming that setting of temperature
selector is 25 °C (77 °F) position.
) B1521Blower speed selector
malfunctionHVAC control module maintains last
normal value.HVAC control module controls actuators
assuming that setting of blower speed
selector is low (1st) position.
) B1522Air flow selector
malfunctionHVAC control module maintains last
normal value.HVAC control module controls actuators
assuming that setting of air flow selector
is DEF position.
[A]
[A]H
L
H
L [B]
[B]
baaba
baaba
I5RW0A722008-01

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-55
Scan Tool DataS6RW0D7224008
As the data values given in the following are standard values estimated on the basis of values obtained from the
normally operation vehicles by using a scan tool, use them as reference values. Even when the vehicles are in good
condition, there may be cases where the checked values do not fall within each specifies data range. Therefore,
judgement as abnormal should not be made by checking with these data alone. ) B1551Serial communication
circuit• HVAC control module maintains last
normal value of outside air
temperature.
4 seconds after, HVAC control
module assuming that outside air
temperature is 20 °C (68 °F).
• HVAC control module maintains last
normal value of engine coolant
temperature.
4 seconds after, HVAC control
module assuming that engine
coolant temperature is 80 °C (176
°F).
• HVAC control module controls
actuators assuming that vehicle
speed is 40 km/h (25 mph).
• HVAC control module controls
actuators assuming that engine type
signal is J20.
• HVAC control module controls
actuators assuming that
combination meter spec signal is
US.HVAC control module controls actuators
assuming that outside air temperature is
20 °C (68 °F), engine coolant
temperature is 80 °C (176 °F), vehicle
speed is 40 km/h (25 mph), engine type
signal is J20 and combination meter spec
signal is US. ) B1552HVAC control module
check sum error
) B1553CAN communication
circuit
) B1557 VSS signal failureHVAC control module controls actuators assuming that vehicle speed is 40 km/h
(25 mph).
) B1561 ECT signal failureHVAC control module maintains last
normal value of engine coolant
temperature. 4 seconds after, HVAC
control module assuming that engine
coolant temperature is 80 °C (176 °F).HVAC control module controls actuators
assuming that engine
coolant temperature is 80 °C (176 °F).
) B1562Outside air
temperature signal
failureHVAC control module maintains last
normal value of outside air
temperature.
4 seconds after, HVAC control module
assuming that outside air temperature
is 20 °C (68 °F).HVAC control module controls actuators
assuming that outside air temperature is
20 °C (68 °F).
) B1570Engine type signal
failureHVAC control module controls actuators assuming that engine type signal is J20.
) B1571Combination meter
spec signal failureHVAC control module controls actuators assuming that combination meter spec
signal is US. DTC No. Trouble AreaFail-Safe Operation
When ignition switch is turned ON
after malfunction is already detectedWhen malfunction is detected during
ignition switch is ON
Scan Tool Data ConditionNormal Condition / Reference
Va l u e
) TEMP CONT
SWITCHIgnition switch turned ON and temperature selector
at maximum cool positionMAX Cool (Selected position of
temperature selector is displayed)
) CABIN
TEMPERATUREIgnition switch turned ON In-car temperature is displayed
) OUTSIDE AIR TEMP Ignition switch turned ON Outside air temperature is displayed
) EVAPORATOR
TEMPIgnition switch turned ON Evaporator temperature is displayed

Downloaded from www.Manualslib.com manuals search engine 7B-56 Air Conditioning System: Automatic Type
Scan Tool Data Definitions
TEMP CONT SWITCH: (Temperature control selector
position, Max Cool, °C / °F, Max Hot): This
parameter indicates the selected position of
temperature control selector.
CABIN TEMPERATURE: (In-car temperature, °C, °F):
This parameter indicates the in-car temperature
detected by inside air temperature sensor.OUTSIDE AIR TEMP (Outside air temperature, °C,
°F): This parameter indicates the outside air
temperature detected by outside air temperature
sensor.
EVAPORATOR TEMP (Evaporator temperature, °C,
°F): This parameter indicates the temperature of air
passed through evaporator.
COOLANT TEMP (Engine Coolant Temperature °C,
°F): This parameter indicates the engine coolant
temperature detected by engine coolant temperature
sensor. ) COOLANT TEMP
Ignition switch turned ONEngine coolant temperature is
displayed
) SUN LOAD Reference value depends on the situation 0 W/m
2 – 1988 W/m2
)MODE CONT
SWITCHIgnition switch turned ON and air flow selector at
AUTO positionAUTO (Selected position of air flow
selector is displayed)
) FAN CONT SWITCHIgnition switch turned ON and blower speed selector
at AUTO positionAUTO (Selected position of blower
speed selector is displayed)
) FAN DESIRED VOLTIgnition switch turned ON and blower speed selector
at HighApprox. 12.0 V
Ignition switch turned ON and blower speed selector
at LowApprox. 4.0 V
) AIR MIX POS SENIgnition switch turned ON and temperature selector
at maximum cool positionApprox. 0.5 V
Ignition switch turned ON and temperature selector
at maximum hot positionApprox. 4.5 V
)MODE POS SENSORIgnition switch turned ON and air flow selector at
DEF positionApprox. 4.5 V
Ignition switch turned ON and air flow selector at
VENT positionApprox. 0.5 V
) A/C CONT SIGA/C switch turned ON, blower speed selector at other
than OFF position with engine runningON
A/C switch turned OFF with engine running OFF
) BLOWER LOAD SIGIgnition switch turned ON, blower speed selector at
other than OFF positionON
Ignition switch turned ON, blower speed selector at
OFF positionOFF
) AIR INTAKE MODEIgnition switch turned ON and air intake selector at
fresh air (FRE) positionFRE
Ignition switch turned ON and air intake selector at
recirculation air (REC) positionREC
Ignition switch turned ON, air flow selector and
blower speed selector at AUTO positionAUTO
) REFRIGERANT
PRESSUREA/C ON (A/C is operating) with engine running at
ambient temperature 30 °C (86 °F)1130 – 1560 kPa (For details, refer to
pressure of high pressure gauge
under “A/C System Performance
Inspection”)
A/C OFF (A/C is not operating) with engine running
at ambient temperature 30 °C (86 °F) and engine
coolant temperature 90 °C (194 °F) – 100 °C (212
°F)600 – 1000 kPa after longer than 10
minute for A/C switch turned off
) A/C COMP CLUTCHA/C switch turned ON, blower speed selector at other
than OFF position with engine runningON
A/C switch turned OFF with engine running OFF
) VEHICLE SPEED At stop with ignition switch turned ON 0 km/h (0 mph)
) ENGINE TYPE Ignition switch turned ON Engine type is displayed.
) METER SPEC Ignition switch turned ONCombination meter spec is displayed. Scan Tool Data ConditionNormal Condition / Reference
Va l u e

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-57
SUN LOAD (W/m2): This parameter indicates the
amount of sunlight detected by sunload sensor.
MODE CONT SWITCH (Air flow selector position,
AUTO, FACE, B/L, FOOT, D/F, DEF): This
parameter indicates the selected position of air flow
selector.
FAN CONT SWITCH (Blower speed selector, AUTO,
OFF, 1st – 8th): This parameter indicates the
selected position of blower speed selector.
FAN DESIRE VOLT (Fan desired voltage, V): This
parameter indicates the consumption voltage of
blower motor.
AIR MIX POS SENSOR (Temperature control
actuator position sensor, V): This parameter
indicates the input signal from position sensor in
temperature control actuator.
MODE POS SENSOR (Air flow control actuator
position sensor, V): This parameter indicates the
input signal from position sensor in air flow control
actuator.
A/C CONT SIG (A/C control signal, ON, OFF): This
parameter indicates the state of A/C switch.BLOWER LOAD SIG (Blower fan load signal, ON,
OFF): ON: Position of blower speed selector is 1st
position or more.
OFF: Position of blower speed selector is OFF
position.
AIR INTAKE MODE (Air intake selector position,
AUTO, FRE, REC): This parameter indicates the
selected position of air intake selector.
REFRIGERANT PRESSURE (A/C refrigerant absolute
pressure, kPa): This parameter indicates the A/C
refrigerant absolute pressure calculated by ECM
A/C COMP CLUCH (A/C compressor magnet clutch,
ON, OFF): This parameter indicates the state of the
A/C compressor magnet clutch.
VEHICLE SPEED (km/h, mph): This parameter
indicates the vehicle speed calculated by ECM.
ENGINE TYPE (Engine type signal, J20, M16 or
M15): This parameter indicates the engine type
signal transmitted by ECM.
METER SPEC (Combination meter spec signal, EU,
UK, US, Canada, DOM): This parameter indicates
the combination meter spec signal transmitted by
combination meter.
Visual InspectionS6RW0D7224009
Check visually the following parts and systems.
DTC B1502: Inside Air Temperature Sensor Circuit MalfunctionS6RW0D7224010
Wiring DiagramInspection item Correction
• Refrigerant leakage and amount
• A/C pipe or hose disconnection,
looseness and
deterioration
• A/C compressor drive belt looseness and damageRefer to “Compressor Drive Belt Inspection
and Adjustment”.
• Battery fluid level and corrosion
of terminal
• Connectors of electric wire harness disconnection and
friction
• Fuses burning
• Parts installation and damage
• Other parts that can be checked visually
5V
G20
1 2 3 4 5 6 7 8 9 10 11 12 13 14
15 16 17 18 19 20 21 24 23 22 25 26 27 28 29 30
ORNORNPNK/BLKG20-10
21
3 [S]
[G]
G20-24
I7RW01722004-01
[S]: Inside air temperature sensor signal circuit 1. HVAC control module 3. To other sensors
[G]: Inside air temperature sensor ground circuit 2. Inside air temperature sensor

Downloaded from www.Manualslib.com manuals search engine 7B-58 Air Conditioning System: Automatic Type
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
NOTE
When DTC B1503, B1504, B1511 and B1512 are indicated together, it is possible that sensor ground
circuit is open.

DTC Detecting Condition Trouble Area
Inside air temperature sensor signal voltage is higher than or lower than
specified value for specified time continuously.• Inside air temperature sensor circuit
• Inside air temperature sensor
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2Wire harness check
1) Turn ignition switch to OFF position.
2) Disconnect connectors from inside air temperature
sensor and HVAC control module.
3) Check for proper connection to each signal circuit
terminal and ground circuit terminal of inside air
temperature sensor and HVAC control module
connectors.
4) If OK, check that inside air temperature sensor circuit is
as follows.
• Wiring harness resistance of each inside air
temperature sensor signal circuit and ground circuit is
less than 3 Ω
• Insulation resistance between inside air temperature
sensor signal circuit and vehicle body ground is
infinity
• Circuit voltage of each inside air temperature sensor
signal circuit and ground circuit is 0 – 1 V with ignition
switch turned ON
Are they in good condition?Go to Step 3. Inside air temperature
sensor signal circuit
and/or ground circuit are
open, short or high
resistance.
3Inside air temperature sensor reference voltage check
1) Connect connector to HVAC control module with ignition
switch turned OFF.
2) Turn ignition switch to ON position.
3) Measure voltage between signal terminal and ground
terminal of inside air temperature sensor connector.
Is voltage 4.5 – 5.5 V?Go to Step 4. Substitute a known-
good HVAC control
module and recheck.
4Inside air temperature sensor check
1) Check inside air temperature sensor for performance
referring to “Inside Air Temperature Sensor Inspection”.
Is it in good condition?Substitute a known-
good HVAC control
module and recheck.Replace inside air
temperature sensor.

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-59
DTC B1503: Evaporator Temperature Sensor Circuit MalfunctionS6RW0D7224011
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
NOTE
When DTC B1502, B1504, B1511 and B1512 are indicated together, it is possible that sensor ground
circuit is open.

5V
G20
1 2 3 4 5 6 7 8 9 10 11 12 13 14
15 16 17 18 19 20 21 24 23 22 25 26 27 28 29 30
ORNORNWHT/BLKG20-9G20-24
[S]
[G] 2
31
I7RW01722005-01
[S]: Evaporator temperature sensor signal circuit 1. HVAC control module 3. To other sensors
[G]: Evaporator temperature sensor ground circuit 2. Evaporator temperature sensor
DTC Detecting Condition Trouble Area
Evaporator temperature sensor signal voltage is higher than or lower than
specified value for specified time continuously.• Evaporator temperature sensor
circuit
• Evaporator temperature sensor
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2Wire harness check
1) Turn ignition switch to OFF position.
2) Disconnect connectors from evaporator temperature
sensor and HVAC control module.
3) Check for proper connection to each signal circuit
terminal and ground circuit terminal of evaporator
temperature sensor and HVAC control module
connectors.
4) If OK, check that evaporator temperature sensor circuit
is as follows.
• Wiring harness resistance of each evaporator
temperature sensor signal circuit and ground circuit is
less than 3 Ω
• Insulation resistance between evaporator temperature
sensor signal circuit and vehicle body ground is
Infinity
• Circuit voltage of each evaporator temperature sensor
signal circuit and ground circuit is 0 - 1 V with ignition
switch turned ON
Are they good condition?Go to Step 3. Evaporator temperature
sensor signal circuit
and/or ground circuit are
open, short or high
resistance.

Downloaded from www.Manualslib.com manuals search engine 7B-60 Air Conditioning System: Automatic Type
DTC B1504: Sunload Sensor Circuit MalfunctionS6RW0D7224012
Wiring Diagram
DTC Detecting Condition and Trouble Area
NOTE
When DTC B1502, B1503, B1511 and B1512 are indicated together, it is possible that sensor ground
circuit is open.

3Evaporator temperature sensor reference voltage check
1) Connect connector to HVAC control module with ignition
switch turned OFF.
2) Turn ignition switch to ON position.
3) Measure voltage between signal terminal and ground
terminal of evaporator temperature sensor connector.
Is voltage 4.5 – 5.5 V?Go to Step 4. Substitute a known-
good HVAC control
module and recheck.
4Evaporator temperature sensor check
1) Check evaporator temperature sensor for performance
referring to “Evaporator Temperature Sensor
Inspection”.
Is it in good condition?Substitute a known-
good HVAC control
module and recheck.Replace evaporator
temperature sensor. Step Action Yes No
G20
1 2 3 4 5 6 7 8 9 10 11 12 13 14
15 16 17 18 19 20 21 24 23 22 25 26 27 28 29 30
PNK
ORNORN
G20-25
G20-24
2
[S]
[G]15V
3
I7RW01722006-01
[S]: Sunload sensor signal circuit 1. HVAC control module 3. To other sensors
[G]: Sunload sensor ground circuit 2. Sunload sensor
DTC Detecting Condition Trouble Area
• Sunload sensor signal voltage is higher than or lower than specified value
for specified time continuously.
• Without sunlight• Sunload sensor circuit
• Sunload sensor
• HVAC control module