2005 SUZUKI SWIFT Inspection

Downloaded from www.Manualslib.com manuals search engine 7B-62 Air Conditioning System: Automatic Type
DTC B1541: HVAC Control Module Back-Up Power Supply MalfunctionS7RS0B7224017
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting11
Position sensor circuit check
1) Check air flow control actuator position sensor circuit
referring to Step 1 to Step 5 and Step 10 to Step 11 of
“DTC B1512: Air flow Control Actuator (Position Sensor)
and/or Its Circuit Malfunction”.
Is it in good condition? Go to Step 12. Repair circuit.
12 Air flow control actuator check
1) Check air flow control actuator referring to “Air Flow
Control Actuator Inspection”.
Is it in good condition? HVAC control module
faulty.
Air flow control actuator
faulty.
Step Action Yes No
WHT/RED
2 17812910
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G51
3
G52-16
I5RS0A722015-01
1. HVAC control module
2. Junction block assembly 3. Circuit fuse
DTC Detecting Condition Trouble Area
Back-up power supply voltage is lo wer than specified value continuously. • Battery voltage supply circuit
• HVAC control module
StepAction YesNo
1 DTC check
1) Turn ON ignition switch for 20 sec. or more.
2) Ignition switch turned OF F and connect scan tool to
DLC.
3) Turn ON ignition switch and check DTC.
Is there DTC B1541? Go to Step 2.
Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
2 Battery voltage supply circuit check
1) Disconnect connector from HVAC control module with
ignition switch turned OFF.
2) Check for proper connection to HVAC control module connector at “G52-16” terminal.
3) If OK, measure voltage between “G52-16” terminal of HVAC control module connector and vehicle body
ground.
Is voltage 10 – 14 V? HVAC control module
faulty.
Circuit fuse blown and/
or “WHT/RED” wire
circuit open or short.

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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
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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

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DTC Troubleshooting
DTC B1553: CAN Communication Signal MalfunctionS7RS0B7224021
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
DTC B1557: Vehicle Speed Sensor Signal MalfunctionS7RS0B7224022
DTC Detecting Condition and Trouble Area
DTC TroubleshootingStep Action Yes No
1 Serial 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” varies displayed on scan
tool.
Is displayed each va ries described varies in “Scan Tool
Data”? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 2.
2 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
HVAC control module receives error code fr om BCM continuously.• CAN communication circuit
• BCM (included in junction block assembly)
•ECM
• HVAC control module
Step Action YesNo
1 DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check ECM and BCM for DTC.
Is there DTC(s)? Go to applicable DTC
diag. flow.
Substitute a known-
good HVAC control
module and recheck.
DTC detecting condition
Trouble area
HVAC control module receives error code from BCM continuously. • VSS circuit
• VSS
• HVAC control module
Step Action YesNo
1 DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Check ECM for DTC.
Is there DTC P0500? Go to “DTC P0480: Fan
1 (Radiator Cooling
Fan) Control Circuit in
Section 1A”.
Substitute a known-
good HVAC control
module and recheck.

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Inspection of HVAC Control Module and Its CircuitS7RS0B7224026
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.

7812910
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1
2
I5RS0A722017-02
1. HVAC control module2. HVAC control module connector (viewed from harness side)
Terminal Wire Color CircuitNormal
Vo l ta g e Condition
G51-1 BRN/WHT Air flow control actuator
(DEF) 10 – 14 V
Ignition switch turned ON, ai
r flow control actuator is
working in operation fr om VENT to DEF position
0 – 1 V Ignition switch turned ON, except the above condition
G51-2 BRN/YEL Air flow control actuator
(FACE) 10 – 14 V
Ignition switch turned ON, ai
r flow control actuator is
working in operation fr om DEF to VENT position
0 – 1 V Ignition switch turned ON, except the above condition
G51-3 GRY/BLU Temperature control
actuator (COOL) 10 – 14 VIgnition switch turned ON, temperature control
actuator is working in ope
ration from HOT to COOL
position
0 – 1 V Ignition switch turned ON, except the above condition
G51-4 GRY/RED Temperature control
actuator (HOT) 10 – 14 VIgnition switch turned ON, temperature control
actuator is working in operation from COOL to HOT
position
0 – 1 V Ignition switch turned ON, except the above condition
G51-5 PPL/WHT Serial communication line
of data link connector 10 – 14 V Ignition switch turned ON
G51-6 — — — —
G51-7 YEL Serial communication line
of BCM Refer to “Inspection of BCM a
nd its Circuits in Section 10B”

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A/C System Performance InspectionS7RS0B7224027
Refer to “A/C System Performance Inspection”.
A/C System Inspection at ECMS7RS0B7224028
Voltage Check
ECM and its circuits can be checked by measuring voltage with special tool connected.
CAUTION!
• ECM connectors are waterproofed. Each terminal of the ECM connectors is sealed up with the
grommet. Therefore, do not measure circuit voltage and resistance by inserting the tester’s probe
into the sealed terminal at the harness side. Or, ECM and its circuits may be damaged by water.
• ECM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with couplers disconnected from ECM.

1) Remove ECM (1) from its bracket by referring to “Electric Throttle Body System Calibration in Section 1C”.
2) Connect special tool (2) between ECM and ECM connectors securely.
3) Check voltage at each terminal.
NOTE
As each terminal voltage is affected by the battery voltage, confirm that the battery voltage is 11 V or
more when ignition sw itch is ON position.

Terminal arrangement of ECM coupler (Viewed from harness side)
1
2
I5RS0A722018-01
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
I4RS0A720010-01

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-73
HVAC Unit Removal and InstallationS7RS0B7226003
Refer to “HVAC Unit Removal and Installation”.
Temperature Control Actuator Removal and
Installation
S7RS0B7226004
Removal1) Disconnect negative (–) cable at battery.
2) Remove steering column hol e cover from instrument
panel.
3) Remove foot duct from HVAC unit.
4) Disconnect temperature control actuator connector (1).
5) Detach temperature control actuator rods (2) from linkage (3).
6) Remove temperature control actuator (4) from HVAC unit.
Installation
Reverse removal procedure.
Temperature Control Actuator InspectionS7RS0B7226005
1) Remove temperature control actuator from HVAC unit referring to “Temperature Control Actuator
Removal and Installation”.
2) Connect connector to temperature control actuator.
3) Set temperature selector of HVAC control module to MAX HOT position with ignition switch ON, and
make sure if the position of actuator lever is MAX
HOT position (A).
4) Turn ignition switch OFF, and then disconnect connector from temperature control actuator.
5) Measure resistance between terminal “3” and “5”.
Temperature control actuator resistance between
terminal “3” and “5” (MAX HOT position)
Approximately 2.5 k Ω at 25 °C (77 °F) 6) Connect connector to tem
perature control actuator.
7) Set temperature selector of HVAC control module to MAX COOL position with ignition switch ON, and
make sure if the position of actuator lever is MAX
COOL position (B).
8) Turn ignition switch OFF, and then disconnect connector from temperature control actuator.
9) Measure resistance between terminal “3” and “5”
Temperature control actuator resistance between
terminal “3” and “5” (MAX COOL position)
Approximately 4.8 k Ω at 25 °C (77 °F)
If check result is not satisfactory, replace the actuator
with new one.
2. Blower upper case 9. Blower motor controller 16. Evaporator 23. Temperature control actuator
3. Air intake control actuator 10. Blower lower case 17. O-ring24. Air flow control actuator
4. Air filter (if equipped) 11. Blower motor 18. Expansion valve25. Inside air temperature sensor
5. Heater unit upper case 12. Heater unit lower case 19. Evaporator temperature sensor 26. Aspirator hose
6. Foot duct 13. Heater core 20. Packing : Do not reuse.
7. Air flow control door assembly 14. Temperature control links 21. Filter cover
1
2
2
3
4
I5RS0A722020-02
I5RS0A722021-03
I5RS0A722022-03

Downloaded from www.Manualslib.com manuals search engine 7B-74 Air Conditioning System: Automatic Type
Air Flow Control Actuator Removal and
Installation
S7RS0B7226006
Removal1) Disconnect negative (–) cable at battery.
2) Remove steering column hol e cover from instrument
panel.
3) Remove foot duct from HVAC unit.
4) Disconnect air flow contro l actuator connector (2).
5) Remove air flow control actuator (1) from HVAC unit, and then detach air flow actuator rod from linkage.
Installation
Reverse removal procedure.
Air Flow Control Actuator InspectionS7RS0B7226007
1) Remove air flow control actuator from HVAC unit referring to “Air Flow C ontrol Actuator Removal and
Installation”.
2) Connect actuator connector to the actuator.
3) Set air flow selector of HVAC control module to DEF position with ignition switch ON, and make sure if the
position of actuator lever is DEF position (8).
4) Turn ignition switch OFF, and then disconnect connector from air flow control actuator.
5) Measure resistance between terminal “3” and “5”
Air flow control actuator resistance between
terminal “3” and “5” (DEF position)
Approximately 4.8 k Ω at 25 °C (77 °F)
I5RS0A722023-03
[A]: LH steering vehicle [B]: RH steering vehicle
8
[A]
[B]
8
7654 321
I5RS0C722004-01