2006 SUZUKI SX4 Ecm

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-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-70 Air Conditioning System: Automatic Type
DTC B1546: A/C Refrigerant Pressure MalfunctionS6RW0D7224019
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1551: Serial Communication Circuit MalfunctionS6RW0D7224020
Wiring DiagramDTC detecting condition Trouble area
• A/C refrigerant pressure sensor signal voltage is lower than specified value
even though outside air temperature is higher than specified value for
specified time continuously.
• Insufficient refrigerant in A/C system• Insufficient of refrigerant
• A/C refrigerant pressure sensor
• Outside 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”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ignition switch to ON position and check DTC in
BCM.
Is DTC B1141 or B1142 (BCM) detected?Go to applicable DTC
diag. flow.Go to Step 3.
3DTC check
Check DTC in ECM.
Is DTC P0532 or P0533 detected?Go to applicable DTC
diag. flow.Go to Step 4.
4A/C refrigerant pressure and outside air temperature
data check
1) Start engine and select “DATA LIST” mode on scan tool.
2) Check “Refrigerant Pressure” and “Outside Air Temp”
displayed on scan tool.
Are values of A/C refrigerant pressure sensor and outside air
temperature within specified ranges indicated in “Scan Tool
Data”?Substitute a known-
good HVAC control
module and recheck.Check the amount of
refrigerant and system
for leaks.
12V
G20
G20-13YEL
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
1
2 3
[S]WHT/REDWHTG20-7
12V5V
[B]4 4
I7RW01722012-02
[B]: Back-up power supply circuit 1. HVAC control module 3. Information display
[S]: Serial communication circuit 2. BCM 4. Circuit fuse

Downloaded from www.Manualslib.com manuals search engine 7B-72 Air Conditioning System: Automatic Type
DTC B1552: HVAC Control Module Check Sum ErrorS6RW0D7224021
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1553: CAN Communication Circuit MalfunctionS6RW0D7224022
DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
Data received by HVAC control module from BCM is erroneous continuously. • BCM
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2Serial communication signal data 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”, “Vehicle Speed”, “Coolant
Temp” and “Outside Air Temp” displayed on scan tool.
Are values of A/C refrigerant pressure sensor and outside air
temperature within specified ranges indicated in “Scan Tool
Data”?Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”Substitute a known-
good HVAC control
module and recheck.
If DTC is still detected
substitute a known-
good BCM and recheck.
DTC detecting condition Trouble area
HVAC control module receives error code from BCM continuously. • CAN communication circuit
•BCM
•ECM
• Combination meter
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check DTC in BCM.
Is DTC U0073 (No.0073), U0100 (No.0100) and/or U0155
(No.0155) detected?Go to applicable DTC
diag. flow.Substitute a known-
good HVAC control
module and recheck.

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-73
DTC B1557: VSS Signal FailureS6RW0D7224023
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1561: ECT Signal FailureS6RW0D7224024
DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
HVAC control module receives invalid data of VSS signal from BCM. • VSS circuit
• VSS
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check DTC in ECM.
Is DTC P0500 detected?Go to applicable DTC
diag flow.Substitute a known-
good HVAC control
module and recheck.
DTC detecting condition Trouble area
HVAC control module receives invalid data of ECT signal from BCM. • ECT sensor circuit
• ECT sensor
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check DTC in ECM.
Is DTC P0116, P0117 or P0118 detected?Go to applicable DTC
diag. flow.Substitute a known-
good HVAC control
module and recheck.

Downloaded from www.Manualslib.com manuals search engine 7B-74 Air Conditioning System: Automatic Type
DTC B1562: Outside Air Temperature Signal FailureS6RW0D7224025
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1563: A/C Refrigerant Pressure Signal FailureS6RW0D7224026
DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
HVAC control module receives invalid data of outside air temperature signal
from BCM.• Outside air temperature sensor
circuit
• Outside 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”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check DTC in BCM.
Is DTC B1141 or B1142 detected?Go to applicable DTC
diag. flow.Substitute a known-
good HVAC control
module and recheck.
DTC detecting condition Trouble area
HVAC control module receives invalid data of A/C refrigerant pressure signal
from BCM.• A/C refrigerant pressure sensor
circuit
• A/C refrigerant pressure sensor
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check DTC in ECM.
Is DTC P0532 or P0533 detected?Go to applicable DTC
diag. flow.Substitute a known-
good HVAC control
module and recheck.

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-75
DTC B1570: Engine Type Signal FailureS6RW0D7224027
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1571: Combination Meter Spec Signal FailureS6RW0D7224028
DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
HVAC control module receives invalid data of engine type signal from BCM. • CAN communication circuit
• HVAC control module
•ECM
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2Scan tool data check
1) Connect scan tool with ignition switch turned OFF
position.
2) Ignition switch turned ON and select “DATA LIST” mode.
3) Check “ENGINE TYPE” displayed on scan tool.
Is value of engine type signal within specified ranges
indicated in “Scan Tool Data”?Substitute a known
good HVAC control
module and recheck.Go to step 3.
3Scan tool data check
1) Check “ENGINE TYPE” displayed on scan tool.
Is “CAN Err” displayed on scan tool data?Check CAN
communication circuit
referring to “DTC Check
in Section 1A”.Substitute a known
good ECM and recheck.
DTC detecting condition Trouble area
HVAC control module receives invalid data of Combination meter spec signal
from BCM.• CAN communication circuit
• Combination meter
• HVAC control module
Step Action Yes No
1Was “Air Conditioning System Check” performed?Go to Step 2. Go to “Air Conditioning
System Check”.
2Scan tool data check
1) Connect scan tool with ignition switch turned OFF
position.
2) Ignition switch turned ON and select “DATA LIST” mode.
3) Check “METER SPEC” displayed on scan tool.
Is value of combination meter spec signal within specified
ranges indicated in “Scan Tool Data”?Substitute a known
good HVAC control
module and recheck.Go to step 3.
3Scan tool data check
1) Check “METER SPEC” displayed on scan tool.
Is “CAN Err” displayed on scan tool data?Check CAN
communication circuit
referring to “DTC Check
in Section 1A”.Substitute a known
good combination meter
and recheck.

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-79
Reference waveform No. 1
Rear defogger switch or A/C switch signal (1)Reference waveform No. 2
Serial communication line of BCM (1)
A/C System Inspection at ECMS6RW0D7224030
When checking voltage at ECM terminals related to A/C system, refer to “Inspection of ECM and Its Circuits in Section
1A”.
Repair Instructions
Operation Procedure for Refrigerant ChargeS6RW0D7226001
Refer to “Operation Procedure for Refrigerant Charge”.Measurement terminal Rear defogger switch
CH1: “G20-4” to “G20-23” A/
C switch
CH1: “G20-21” to “G20-23”
Oscilloscope setting CH1: 5 V / DIV
TIME: 10 ms / DIV
Measurement condition Rear defogger switch:
• Ignition switch is at ON
position and rear defogger
switch is not pushed
A/C switch:
• Ignition switch is at ON
position and A/C switch is
not pushed
I7RW01722014-02
Measurement terminal CH1: “G20-13” to “G20-23”
Oscilloscope setting CH1: 5 V / DIV
TIME: 20 ms / DIV
Measurement condition Ignition switch is at ON
position
I7RW01722015-02