Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Manual Type 7B-25
HVAC Unit ComponentsS6RW0D7216007
NOTE
The figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are installed
at the opposite side.
1
10
1
9
8
25
25
3
20
3
19 19
19
24
24 21
4
23*27 15 16* 14
25*18*2
2526
17*1312 11
5*22
67
*
26
5*
I6RW0C721006-01
1. Blower upper case 8. Air intake control actuator 15. Evaporator 22. Temperature control door
assembly
2. Blower lower case 9. Air intake control link 16. Evaporator temperature sensor 23. Drain hose
3. Heater unit upper case 10. Air intake control door 17. Expansion valve 24. Cable lock clamp
4. Heater unit lower case 11. Blower motor 18. Expansion pipe 25. Packing
5. Foot duct 12. Blower motor cap 19. Air flow control lever 26. O-ring
: Apply compressor oil.
6. HVAC air filter (if equipped) 13. Blower motor resister 20. Air flow control door assembly 27. Resistance board (non-A/C)
Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-39
General Description
Auto A/C System DescriptionS6RW0D7221001
The automatic type air conditioning system (auto A/C) is provided with the function to automatically control the inside
air temperature, fan speed, air flow outlet direction and air intake position by HVAC control module in addition to
functions of the manual type air conditioning system (manual A/C). Once the inside air temperature is set using the
temperature selector, HVAC control module automatically controls the inside air temperature at the constant level at all
times based on the inside air temperature, outside air temperature, amount of sunlight and engine coolant
temperature detected respectively by the inside air temperature sensor, outside air temperature sensor, sunload
sensor and ECT sensor. For the electronic control system components location, refer to “Electronic Control System
Components Location”. For the A/C system components location, refer to “A/C System Major Components Location”.
Auto A/C Electronic Control Input / Output Table
Temperature selector
MODE (air flow) selector
Blower speed selector
Air intake selector
AUTO switch A/C switch
Outside air
temperature
sensor
A/C refrigerant pressure sensor
Compressor relay
Blower motor controller
Temperature control actuator
Air flow control actuator
Air intake control actuator
BCM
ECM
Data link connector
HVAC control module
CPU
ECT sensor
Sunload sensor
Inside air temperature sensor
Evaporator temperature sensor
Condenser cooling fan relay
Wheel
speed
sensor
*
*
*
Combination meterABS control module
I6RW0C722001-01
*: CAN communication
Downloaded from www.Manualslib.com manuals search engine 7B-40 Air Conditioning System: Automatic Type
HVAC Control DescriptionS6RW0D7221002
Temperature Control
HVAC control module calculates the target temperature
control door position based on signals from the
temperature selector, inside air temperature sensor,
outside air temperature sensor and sunload sensor and
controls the temperature control actuator so that the
current position of the temperature control door matches
its target position.
Fan Speed Control
HVAC control module calculates the target blower fan
speed based on signals from the temperature selector,
inside air temperature sensor, outside air temperature
sensor, ECT sensor and sunload sensor, compares it
with the current blower fan speed inputted from the
blower motor controller to control the current blower fan
speed to the target level.
Air Flow Outlet Control
HVAC control module calculates the target temperature
control door position based on signals from the
temperature selector, inside air temperature sensor,
outside air temperature sensor, ECT sensor and sunload
sensor. Using thus obtained target temperature control
door position, it further calculates the target air flow
control door position and controls the air flow control
actuator so that the current air flow control door position
becomes the target position.
Air Intake Position Control
HVAC control module determines the position of the air
intake control door based on signals from the
temperature selector, inside air temperature sensor,
outside air temperature sensor and sunload sensor and
selects any of the following positions by controlling the
position of the air intake control door.
• FRESH position (FRE)
• RECIRCULATION position (REC)
• MIX position (MIX)A/C Compressor Relay Control
HVAC control module outputs A/C switch ON signal to
ECM via BCM when the vehicle state satisfy conditions
described below.
• A/C switch is ON
• Evaporator temperature is higher than specified value
• Evaporator temperature sensor malfunction is not
detected
Communication of ECM and BCM is established by CAN
(Controller Area Network). (For more detail of CAN
communication, refer to “CAN Communication System
Description in Section 1A”).
ECM turns ON the A/C compressor relay when the
vehicle state satisfy conditions described below.
• A/C switch ON signal is inputted
• A/C refrigerant pressure is within specified range
• Engine speed is within specified range
• Engine coolant temperature is lower than specified
value
• Throttle opening is lower than specified value
• Vehicle is not in either state of starting or quick
acceleration
• ECT sensor malfunction is not detected
• A/C refrigerant pressure sensor malfunction is not
detected
Condenser Cooling Fan Relay Control
ECM turn ON the condenser cooling fan relay at the
same time when ECM turn ON the A/C compressor
relay.
Sub-Cool A/C System DescriptionS6RW0D7221003
Refer to “Sub-Cool A/C System Description”.
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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Component Location
A/C System Major Components LocationS6RW0D7223001
Refer to “A/C System Major Components Location”.
[A]: Illumination control model 10. Air intake actuator 22. Compressor 34. “A/C” indicator light
[B]: Junction block with BCM 11. Air flow control actuator 23. HVAC control module 35. Rear defogger switch
[C]: Junction block without BCM 12. Temperature control actuator 24. BCM 36. Rear defogger indicator
1. Main fuse box 13. Inside air temperature sensor 25. A/C refrigerant pressure sensor 37. To other control module
2. Ignition switch 14. Outside air temperature sensor 26. Condenser cooling fan relay 38. Indicator light, switch,
selector
3. CAN junction connector 15. Evaporator temperature sensor 27. Information display 39. “FRE” indicator light
4. Rear defogger relay 16. Sunload sensor 28. Lighting switch 40. “REC” indicator light
5. Rear defogger 17. Junction block assembly 29. A/C switch 41. Temperature selector
6. Blower motor relay 18. ECM 30. Air intake selector 42. Blower speed selector
7. Blower motor 19. ECT sensor 31. To BCM 43. MODE (air flow) selector
8. Blower motor controller 20. Condenser cooling fan motor 32. ABS control module 44. Tail light
9. DLC 21. Compressor relay 33. Illumination light 45. Main relay
Downloaded from www.Manualslib.com manuals search engine 7B-44 Air Conditioning System: Automatic Type
Electronic Control System Components LocationS6RW0D7223002
NOTE
The figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are installed
at the opposite side.
[A]
2
3
5
1
4
78*
18
19
20
23
22 219*
10*
11*
12*
13*
15* 16* 17
14*
8*6
I6RW0C722003-01
[A]: Junction block assembly viewed from relay
side8. Junction block assembly 16. Blower motor controller
1. A/C refrigerant pressure sensor 9. Sunload sensor 17. HVAC control module
2. Compressor relay 10. Inside air temperature sensor 18. Temperature selector
3. Condenser cooling fan relay 11. Air flow control actuator 19. Blower speed selector
4. Outside air temperature sensor 12. Temperature control actuator 20. MODE (air flow) selector
5. ECT sensor 13. Evaporator temperature sensor 21. A/C switch
6. Condenser cooling fan 14. Air intake actuator 22. Air intake selector
7. Blower motor relay 15. Blower motor 23. Rear defogger switch
Downloaded from www.Manualslib.com manuals search engine 7B-46 Air Conditioning System: Automatic Type
Description for Each Step
Step 1. Customer complaint analysis
Talk to customer, and then record details of the problem.
Customer questionnaire (Example)
NOTE
The form is a standard sample. It should be modified according to conditions characteristic of each
market.
Step 2. Visual inspection
As a preliminary step, be sure to perform visual check of
the items that support proper function of the air
conditioning system referring to “Visual Inspection”.
Step 3. DTC check
Check DTC referring to “DTC Check”.
Step 4. DTC troubleshooting
Based on the DTC, perform an applicable DTC
diagnostic flow and locate the cause of the trouble,
namely in a sensor, wire harness, connector, actuator,
HVAC control module or other part and repair faulty
parts.
Step 5. A/C system performance inspection
Inspect A/C system suspected to be a possible cause
referring to “A/C System Performance Inspection”.Step 6. A/C system symptom diagnosis
Check any part or system suspected to be a possible
cause referring to “A/C System Symptom Diagnosis”.
Step 7. Check for intermittent problem
Check any part where an intermittent trouble is easy to
occur (e.g., wire harness, connector, etc.), referring to
“Intermittent and Poor Connection Inspection in Section
00” and related circuit of trouble cord recorded.
Step 8. Final confirmation test
Confirm if the problem symptom is troubleshoot and the
A/C system is free from any abnormal conditions. If there
existed DTC, clear the DTC. Then, check if the DTC is
still detected and if there is any other DTC.
I4RH01722014-01
Downloaded from www.Manualslib.com manuals search engine 7B-48 Air Conditioning System: Automatic Type
Cool air does not come
out or insufficient cooling
(A/C compressor normal
operation)Insufficient or excessive charge of
refrigerantCheck the amount of refrigerant and system
for leaks.
Condenser cloggedCheck condenser referring to “Condenser
Assembly On-Vehicle Inspection”.
A/C evaporator clogged or frostedCheck A/C evaporator and evaporator
temperature sensor referring to “Evaporator
Inspection” and “Evaporator Temperature
Sensor Inspection”.
Evaporator temperature sensor faultyCheck evaporator temperature sensor
referring to “Evaporator Temperature Sensor
Inspection”.
Expansion valve faultyCheck expansion valve referring to “Expansion
Valve Inspection”.
Desiccant cloggedCheck desiccant and cap with filter.
Compressor drive belt loosened or
brokenAdjust or replace drive belt.
Magnet clutch faultyCheck magnet clutch referring to “Magnet
Clutch Inspection”.
Compressor faultyCheck compressor.
Air in A/C systemReplace condenser, and then perform
evacuation and charge referring to “Operation
Procedure for Refrigerant Charge”.
Air leaking from HVAC unit or air ductRepair as necessary.
Heater and ventilation system faultyCheck HVAC unit.
HVAC control module faultyCheck HVAC control module referring to
“Inspection of HVAC Control Module and Its
Circuit”.
Temperature control actuator faultyCheck temperature control actuator referring to
“Temperature Control Actuator and Its Circuit
Inspection”.
Blower motor faultyCheck blower motor referring to “Blower Motor
Inspection in Section 7A”.
Excessive compressor oil in A/C systemDrain excessive compressor oil from A/C
system circuit and compressor.
Cool air does not come
out only intermittentlyWiring connection faultyRepair as necessary.
Expansion valve faultyCheck expansion valve referring to “Expansion
Valve Inspection”.
Excessive moisture in A/C systemReplace condenser, and then perform
evacuation and charge referring to “Operation
Procedure for Refrigerant Charge”.
Magnet clutch faultyCheck magnet clutch referring to “Magnet
Clutch Inspection”.
Excessive amount of refrigerantCheck the amount of refrigerant.
Cool air comes out only at
high speedCondenser cloggedCheck condenser referring to “Condenser
Assembly On-Vehicle Inspection”.
Insufficient charge of refrigerantCheck the amount of refrigerant and system
for leaks.
Air in A/C systemReplace condenser, and then perform
evacuation and charge referring to “Operation
Procedure for Refrigerant Charge”.
Compressor drive belt loosened or
brokenAdjust or replace drive belt.
Compressor faultyCheck compressor.
Cool air does not come
out only at high speedExcessive amount of refrigerantCheck the amount of refrigerant.
A/C evaporator frostedCheck A/C evaporator and evaporator
temperature sensor referring to “Evaporator
Inspection” and “Evaporator Temperature
Sensor Inspection”. Condition Possible cause Correction / Reference Item