check engine light SUZUKI SX4 2006 1.G Service Manual Online

Downloaded from www.Manualslib.com manuals search engine 7B-12 Air Conditioning System: Manual Type
A/C System Inspection at ECMS6RW0D7214003
When checking voltage at ECM terminals related to A/C system, refer to “Inspection of ECM and Its Circuits in Section
1A”.0.05 – 0.15
(0.5 – 1.5)
(4.2 – 21.3)0.7 – 1.0
(7 – 10)
(100 – 142)Both low and high
pressure sides indicate
low readings.
Output air is slightly cold.Insufficient refrigerant
in system
(Refrigerant leaking).Using leak detector,
check for leaks and
repair as necessary.
Recharge refrigerant to
a specified amount.
If the pressure reading
is almost 0 when the
manifold gauges are
attached, check for any
leaks, repair them, and
evacuate the system.
0.4 – 0.6
(4 – 6)
(56.9 – 85.3)Pressure on low pressure
side is high.
Pressure on high pressure
side is low.
Both pressure becoming
equal right after A/C is
turned OFF.Internal leak in
compressor.Inspect compressor
and repair or replace
as necessary.
0.40 – 0.45
(4.0 – 4.5)
(57 – 64)2.0 – 2.5
(20 – 25)
(285 – 355)High pressure reading on
both low and high
pressure sides.Overcharged A/C
system.Adjust refrigerant to
specified amount.
Faulty condenser
cooling operation.Clean condenser.
Faulty condenser
cooling fan operation.Inspect and repair
condenser cooling fan.
High pressure reading on
both low and high
pressure sides.
Low pressure side tubing
is not cold when touched.Presence of air in A/C
system
(Improperly
evacuated).Replace desiccant and
cap with filter.
Inspect quantity of
compressor oil and
presence of
contaminants in oil.
Evacuate system and
recharge with fresh
refrigerant.
0.45 – 0.55
(4.5 – 5.5)
(64 – 78)High pressure reading on
both low and high
pressure sides.
Large amount of frost or
dew on the low pressure
side tubing.Faulty expansion
valve.
Refrigerant flow is not
regulated properly.Replace expansion
valve. Condition
Possible cause Correction Manifold gauge MPa (kgf/cm
2) (psi)
Detail
Lo Hi

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Manual Type 7B-17
Repair Instructions
Operation Procedure for Refrigerant ChargeS6RW0D7216001
WARNING!
• Your eyes should not be exposed to refrigerant (liquid).
Any liquid HFC-134a (R-134a) escaping by accident shows a temperature as low as approximately –
6 °C (21.2 °F) below freezing point. Should liquid HFC-134a (R-134a) is exposed to your eyes, it may
cause a serious injury. To protect your eyes from such accident, it is necessary to always wear
goggles. Should it occur that HFC-134a (R-134a) is exposed to your eyes, consult a doctor
immediately.
– Do not use your hand to rub the affected eye(s). Instead, use fresh cold water to splash it over the
affected area to gradually raise temperature of such area above freezing point.
– Obtain proper treatment as soon as possible from a doctor or eye specialist.
• Should the liquid refrigerant HFC-134a (R-134a) is exposed to your skin, the affected area should be
treated in the same manner as when skin is frostbitten or frozen.
• Do not handle refrigerant near any place where welding or steam cleaning is performed.
• Refrigerant should be kept in a cold and dark place. It should never be stored in any place where
temperature is high, e.g. where exposed to direct sun light, close to fire or inside vehicle (including
trunk room).
• Avoid breathing fume produced when HFC-134a (R-134a) is burned. Such fume may be hazardous to
your health.

Start evacuation.Start evacuation.
Stop evacuation.Stop evacuation.
15 minutes (above -100 kPa)15 minutes (above -100 kPa)
Wait 10 minutesWait 10 minutes
Check A/C system forCheck A/C system for
pressure tighteness.pressure tighteness.
Recharge A/C system withRecharge A/C system withrefrigerant.refrigerant.
Check A/C system for refrigerantCheck A/C system for refrigerantleaks and amount of refrigerantleaks and amount of refrigerantcharged.charged.
Performance testPerformance test
Inspect and repair connections.Inspect and repair connections.
If gauge showsIf gauge showsabnormal conditionsabnormal conditions
Recharge 430 20 g ofRecharge 430 20 g ofrefrigerant.refrigerant.
I5RW0A721011-01

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-41
On-Board Diagnostic System DescriptionS6RW0D7221004
NOTE
The diagnostic information as diagnostic
trouble code (DTC) can be known by using
SUZUKI scan tool. For further details, refer to
“DTC Check”.

HVAC control module detects malfunctions, which may
occur in the following area.
• Inside air temperature sensor
• Evaporator temperature sensor
• Sunload sensor
• Temperature control actuator
• Air flow control actuator
• Temperature selector of HVAC control module
• Air flow selector of HVAC control module
• Blower speed selector of HVAC control module
• Back-up power supply circuit of HAVC control module
• Serial communication line between BCM and HVAC
control module• Received data from BCM as follows
– Outside air temperature sensor signal
– ECT sensor signal
– A/C refrigerant pressure sensor signal
– VSS signal
– Engine type signal
– Combination meter spec signal
– CAN communication circuit failure signal
When HVAC control module detects malfunction, the “A/
C” indicator light (1) flashes to warn and the diagnostic
trouble code (DTC) is stored in the memory of the
module. When diagnosing trouble, the DTC can be
checked according to “DTC Check”.
Schematic and Routing Diagram
A/C System Air Flow DiagramS6RW0D7222001
Refer to “A/C System Air Flow Diagram”.
1
I5RW0A722002-01

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Abnormal Noise Symptom Diagnosis of A/C
System
S6RW0D7224003
Refer to “Abnormal Noise Symptom Diagnosis of A/C
System”.
DTC CheckS6RW0D7224004
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 tool3) Light over sunload sensor vertically with an
incandescent light of approximately 100 W apart
from about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent light, 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). Insufficient air flow of
cooled airA/C evaporator clogged or frostedCheck A/C evaporator and evaporator
temperature sensor referring to “Evaporator
Inspection” and “Evaporator Temperature
Sensor Inspection”.
Air leaking from HVAC unit or air ductRepair as necessary.
Blower motor faultyCheck blower motor referring to “Blower Motor
Inspection in Section 7A”.
Wiring or grounding faultyRepair as necessary. Condition Possible cause Correction / Reference Item(A)
1I5RW0A722004-01

Downloaded from www.Manualslib.com manuals search engine 7B-50 Air Conditioning System: Automatic Type
Not Using SUZUKI Scan Tool
NOTE
In case of malfunction of temperature
selector, blower speed selector and air flow
selector, DTC can not be checked by the
following procedure. Use SUZUKI scan tool
for DTC check.

1) Light over sunload sensor vertically with an
incandescent light of approximately 100 W apart
from about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent light, DTC of sunload sensor is
detected as current DTC even though there is
not any malfunction.

2) Set the following selectors to specified positions
below respectively with ignition switch off position.
• Temperature selector (1) is maximum cool
position
• Blower speed selector (2) is OFF position
• Air flow selector (3) is AUTO position
3) While pressing A/C switch (4) and air intake selector
(5) simultaneously, turn ignition switch to ON
position.
4) Wait for about 5 seconds (start of diagnosis).
5) Read flashing pattern of “FRE” (6) and “REC” (7)
indicator lights which represents DTC and write it
down.
NOTE
• When 2 or more current 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.
• Pressing “A/C” switch alternates display
of current DTC and history DTC. “A/C”
indicator light (8) remains off when display
is in current DTC mode and it lights up
when display is in history DTC mode.
• When a history DTC is indicated while 2 or
more history DTCs are detected, it is
possible to have other history DTC(s)
stored in HVAC control module displayed
by pressing the air intake selector.

Example: When inside air temperature sensor
circuit malfunction (Open) is set
Example: When VSS signal failure (Data error) is
set
6) After completing above check, turn ignition switch to
“OFF” position.
[A]: “REC” indicator light L: OFF
[B]: “FRE” indicator light a. About 0.5 seconds
H: ON b. About 2 seconds
[A]: “REC” indicator light a. About 0.5 seconds
[B]: “FRE” indicator light b. About 3 seconds
H: ON c. About 1.5 seconds
L: OFF
123
458
6
7I5RW0A722005-01
[A]
[B]H
L
H
L [B]
[A]
ab
aI5RW0A722006-02
[A]
[B]H
L
H
L [B]
[A]
ab
aaaa
c
I5RW0A722025-01

Downloaded from www.Manualslib.com manuals search engine 7B-52 Air Conditioning System: Automatic Type
DTC TableS6RW0D7224006
CAUTION!
Be sure to perform “Air Conditioning System Check” before starting diagnosis.

NOTE
• History DTC is such DTC which HVAC control module saves in its memory when it detects current
DTC for 60 seconds or more continuously.
• DTC B1504, B1541, B1546, B1570 and B1571 are displayed as a current DTC only when a current
malfunction is detected.
• When HVAC control module detects DTC B1513 and B1514, both current and history DTCs are
displayed at the same time.

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
) B1502Inside Air
Temperature
Sensor Circuit
Malfunction21Signal voltage of inside air temperature sensor is
higher than specification.Flashed
22Signal voltage of inside air temperature sensor is
lower than specification.Flashed
) B1503Evaporator
Temperature
Sensor Circuit
Malfunction31Signal voltage of evaporator temperature sensor is
higher than specification. Flashed
32Signal voltage of evaporator temperature sensor is
lower than specification.Flashed
) B1504Sun load Sensor
Circuit
Malfunction41• Signal voltage of sun load sensor is higher than
specification.
• Without sunlight.—
42Signal voltage of sun load sensor is lower than
specification.Flashed
) B1511Temperature
Control Actuator
(Position Sensor)
and/or Its Circuit
Malfunction61Signal voltage of position sensor included in
temperature control actuator is higher than
specification.Flashed
62Signal voltage of position sensor included in
temperature control actuator is lower than
specification.Flashed
) B1512Air Flow Control
Actuator
(Position Sensor)
and/or Its Circuit
Malfunction71Signal voltage of position sensor included in airflow
control actuator is higher than specification. Flashed
72Signal voltage of position sensor included in airflow
control actuator is lower than specification.Flashed
) B1513Temperature
Control Actuator
(Motor) and/or Its
Circuit
Malfunction63
Motor of temperature control actuator is not
operated more than specified time.Flashed
) B1514Air Flow Control
Actuator (Motor)
and/or Its Circuit
Malfunction73Motor of air flow control actuator is not operated
more than specified time.Flashed
) B1520Temperature
Selector
Malfunction15 1Signal voltage of temperature selector in HVAC
control module is higher than specification.Flashed
15 2Signal voltage of temperature selector in HVAC
control module is lower than specification.Flashed

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) 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 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-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

Downloaded from www.Manualslib.com manuals search engine 7B-76 Air Conditioning System: Automatic Type
Inspection of HVAC Control Module and Its CircuitS6RW0D7224029
HVAC control module and its circuits can be checked at HVAC control module wiring couplers by measuring voltage.
CAUTION!
HVAC control module can not be checked by itself. It is strictly prohibited to connect voltmeter to
HVAC control module with couplers disconnected from it.

Voltage Check
1) Remove HVAC control module referring to “HVAC Control Module Removal and Installation”.
2) Check voltage at each terminal.
NOTE
As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when ignition
switch is ON.

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
12
I7RW01722013-01
1. HVAC control module 2. HVAC control module connector (viewed from harness side)
Terminal Wire Color CircuitNormal
Vo l ta g eCondition
G20-1 GRY/BLUTemperature control
actuator (COOL)10 – 14 VIgnition switch turned ON, temperature control
actuator is working in operation from HOT to COOL
position
0 – 2 VIgnition switch turned ON, except the above
condition
G20-2 GRY/REDTemperature control
actuator (HOT)10 – 14 VIgnition switch turned ON, temperature control
actuator is working in operation from COOL to HOT
position
0 – 2 VIgnition switch turned ON, except the above
condition
G20-3 BLUSerial communication line
of data link connector10 – 14 V Ignition switch turned ON
G20-4 GRN/YEL Rear defogger switchRefer to “Reference waveform No. 1: Automatic Type”.
G20-5 BLK/YEL Illumination ground 0 – 1 V Full-time
G20-6 RED/YEL Illumination switch0 – 1 VIgnition switch turned ON, lighting switch OFF
position
10 – 14 V Ignition switch turned ON, lighting switch ON position
G20-7 WHT/REDElectric power source for
back-up10 – 14 V Constantly