Page 993 of 1496

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-45
NOTE
When no current DTC is detected, all contents displayed on display (1) of HVAC control module and 
defroster indicator (2) flash at the same time.
 
Fail-Safe TableS7RS0B7224006
When any of the following malfunctions (DTCs) is detected, fail-safe mode is activated.
However, when HVAC control module detects normal ope ration of A/C system, fail-safe mode is cancelled.
 )
 B1562 14 18 18 Outside air temperatur e sensor signal malfunction Flashed
 )  B1563 d4 20 19 A/C refrigerant pressure sensor signal malfunction —
— See NOTE 
below 
(current  DTC) ——Normal —
00 (history  DTC)
DTC No. 
(displayed  on 
SUZUKI 
scan tool) DTC 
(indicated  on 
display of  HVAC 
control 
module) Priority of 
display 
(current  DTC) Priority 
of 
display 
(history  DTC) Diagnosis
“AUTO” 
indicator  lamp
1
2
I5RS0A722009-01
DTC No.
Trouble Area Fail-Safe Operation
 )
B1502 Inside air temperature sensor and/
or its circuit HVAC control module controls actu
ators assuming that inside air 
temperature is 25 ° C (77 °F).
 )
B1503 A/C evaporator temperature sensor 
and its circuit • HVAC control module turn
s off A/C switch signal.
• HVAC control module controls actu ators assuming that evaporator 
temperature is 0 ° C (32 °F).
 )
B1504 Sunload sensor and/or its circuit HVAC control module controls actu
ators assuming that amount of 
sunlight is 0 W/m
2.
 ) B1551 Serial communication circuit
HVAC control module controls actuators assuming that outside air 
temperature is 20 ° C (68 °F), engine coolant temperature is 80  °C 
(176  °F), and vehicle speed is 40 km/h (25 mph).
 )
B1552 Serial communication circuit
 )
B1553 CAN communication circuit
 )
B1557 Vehicle speed sensor and/or its 
circuit HVAC control module controls act
uators assuming that vehicle speed 
is 40 km/h (25 mph).
 )
B1561 Engine coolant temperature sensor 
and/or its circuit HVAC control module controls act
uators assuming that engine coolant 
temperature is 80 ° C (176 °F).
 )
B1562 Outside air temperature sensor 
and/or its circuit HVAC control module controls actu
ators assuming that outside air 
temperature is 20 ° C (68 °F).  
         
        
        
     
        
        Page 994 of 1496

Downloaded from www.Manualslib.com manuals search engine 7B-46 Air Conditioning System: Automatic Type
Scan Tool DataS7RS0B7224007
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 ma de by checking with these data alone.
Scan Tool Data Condition Normal Condition / Reference 
Va l u e
 )  TEMP CONT 
SWITCH Each reference value is relative to the position of 
temperature selector of HVAC control module. Max Cool, 18.5 
°C (65 ° F), 19 °C (66 
° C) – 31  °C (88  °F), 31.5  °C (89  °F), 
Max Hot
 )  CABIN 
TEMPERATURE Reference value is relative to in-car temperature. –6.5 
°C – 57.25 ° C 
(20.3  °F – 135.05  °F)
 )  OUTSIDE AIR TEMP Reference value is relative to outside air 
temperature. –23.3 
°C – 65.95  °C 
(–9.94  °F – 150.71  °F)
 )  EVAPORATOR 
TEMP Reference value is relative to temperature of 
evaporator. –29.7 
°C – 59.55  °C 
(–21.46  °F – 139.19  °F)
 )  COOLANT TEMP At specified id le speed after warming up. 80 °C – 100  °C (176 ° F – 212 ° F)
 )  SUN LOAD Reference value depends on the situation. 0 W/m
2 – 4447.8 W/m2
 )MODE CONT 
SWITCH Each reference value is relative to the position of air 
flow selector of HVAC control module.
AUTO, FACE, B/L, FOOT, D/F, DER
 )  FAN CONT SWITCH Each reference value is relative to the position of 
blower speed selector of HVAC control module. AUTO, OFF, 1st, 2nd – 7th, 8th
 )  FAN DESIRED VOLT Reference value is relative to the position of blower 
speed selector of HVAC control module. 0 – 16.0 V
 )  AIR MIX POS SEN Reference value is relative to the position of 
temperature selector of HVAC control module. about 2.0 V (Max Hot)
about 4.0 V (Max Cool)
 ) MODE POS SENSOR Reference value is relative to the position of air flow 
selector of HVAC control module. about 1.6 V (DEF)
about 4.0 V (VENT)
 )  A/C CONT SIG A/C system is ON. ON
A/C system is OFF. OFF
 )  BLOWER LOAD SIG Position of blower speed selector is 1st position or 
more.
ON
Position of blower speed selector is OFF position. OFF
 )  AIR INTAKE MODE Fresh air (FRE) mode is activated. FRE
Recirculation air (REC) mode is activated. REC
AUTO mode is activated. AUTO
 )  REFRIGERANT 
PRESSURE Engine running. A/C ON (A/C is operating) 
at ambient temperature: 
30 
°C (86  °F) 1470 – 1770 kPa For more details, 
refer to pressure  of high pressure 
gauge under “A/C System  Performance Inspection”
A/C OFF (A/C is not 
operating) at ambient 
temperature: 30  °C (86 
° F) and engine coolant 
temperature: 90  ° – 100 
° C 600 – 1000 kPa After longer than 10 
min from A/C switch turned off
 )  A/C COMP CLUTCH Engine running. A/C switch and blower 
motor switch turned ON
ON
A/C switch and/or blower 
motor switch turned OFF OFF
 )  DFR INDICATOR Defroster indicator 
lamp is lighted. ON
Defroster indicator la mp is not lighted. OFF
 )  VEHICLE SPEED At stop. OFF
0 km/h (0 mph)  
         
        
        
     
        
        Page 995 of 1496

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-47
Scan Tool Data Definitions
TEMP CONT SWITCH (TEMPERATURE SELECTOR):   Position of temperature control 
selector of HVAC control module
CABIN TEMPERATURE:   In-car temperature detected 
by inside air temperature sensor installed in HVAC 
control module
OUTSIDE AIR TEMP (OUTSIDE AIR  TEMPERATURE):   Outside air temperature 
detected by outside air temperature sensor installed 
in front bumper member
EVAPORATOR TEMP (EVAPORATOR  TEMPERATURE):   Temperature of air passed 
through evaporator
COOLANT TEMP (ENGINE COOLANT  TEMPERATURE):   Engine coolant temperature 
detected by engine coolant temperature sensor
SUN LOAD:   Amount of sunlight detected by sunload 
sensor installed on the driver side on the dashboard
MODE CONT SWITCH (MODE (AIR FLOW)  SELECTOR):   Position of air flow selector of HVAC 
control module
FAN CONT SWITCH (BLOWER SPEED SELECTOR):   Position of blower speed selector of HVAC control 
module
FAN DESIRED VOLT:   Voltage for blower motor AIR MIX POS SEN (TEMPERATURE CONTROL 
ACTUATOR POSITI ON SENSOR):  Input signal 
from position sensor in temperature control actuator
MODE POS SENSOR (AIR FLOW CONTROL  ACTUATOR POSITI ON SENSOR):  Input signal 
from position sensor in air flow control actuator
A/C CONT SIG (A/C SWITCH SIGNAL, ON or OFF):   State of A/C switch
BLOWER LOAD SIG (BLO WER FAN LOAD SIGNAL, 
ON or OFF):   ON: Position of blower speed selector 
is 1st position or more / OFF: Position of blower 
speed selector is OFF position.
AIR INTAKE MODE (AUTO, FRE or REC):   State of air 
intake mode
REFRIGERANT PRESSURE (A/C REFRIGERANT  ABSOLUTE PRESSURE):   This parameter 
indicates A/C refrigerant absolute pressure 
calculated by ECM
A/C COMP CLUTCH (A/C COMPRESSOR MAGNET  CLUTCH, ON or OFF):   This parameter indicates 
the state of the A/C switch
DFR INDICATOR (DEFROSTER INDICATOR LAMP,  ON or OFF):   State of defroster indicator lamp
VEHICLE SPEED:   It is computed based on pulse 
signals from vehicle speed sensor
Air Conditioning System CheckS7RS0B7224008
Step Action YesNo
1 Customer complaint analysis
1) Perform   )”Customer complaint analysis”.
Was customer complaint analysis performed? Go to Step 2.
Perform customer 
complaint analysis.
2 Visual inspection
1) Perform   )“Visual inspection”.
Is there any faulty condition? Repair or replace 
malfunction part.
Go to Step 3.
3 DTC check
1) Perform   )“DTC check”.
Is there any DTC code? Go to Step 4.
Go to Step 5.
4 Troubleshooting malfunction
1) Perform   ) “Troubleshooting malfunction”.
Is there any faulty condition? Repair or replace 
malfunction part, and go 
to Step 7.
Go to Step 5.
5 Perform A/C system symptom diagnosis
1) Inspect and repair referri ng to “A/C System Symptom 
Diagnosis”.
Is there any faulty condition? Repair or replace 
malfunction part, and go 
to Step 7.
Go to Step 6.
6 Check for intermittent problem
1) Check for intermittent troubles referring to “Intermittent 
and Poor Connection Inspection in Section 00”.
Is there any faulty condition? Repair or replace 
malfunction part, and go 
to Step 7.
Go to Step 7.
7 Final confirmation test
1) Perform   ) “Final confirmation test”.
Is there any malfunction code? Go to Step 4.
End.  
         
        
        
     
        
        Page 996 of 1496

Downloaded from www.Manualslib.com manuals search engine 7B-48 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 from 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 th e items that support proper function of the air conditioning 
referring to “Visual Inspection”.
Step 3. DTC check
Check DTC referring to “DTC Check”.
Step 4. Troubleshooting malfunction
Based on the DTC, perform an applicable  DTC diagnostic flow and locate the cause of the trouble, namely in a sensor, 
wire harness, connector, actuat or, HVAC control module or other part and repair faulty parts.
Step 5. A/C system symptom diagnosis
Check any part or system  suspected to be a possible cause referring to “A/C System Symptom Diagnosis”.
Step 6. Check for intermittent problem
Check any part where an intermittent trouble is easy to oc cur (e.g., wire harness, connector, etc.), referring to 
“Intermittent and Poor Connection Inspection in Sect ion 00” and related circuit of trouble cord recorded.
I4RH01722014-01  
         
        
        
     
        
        Page 997 of 1496

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-49
Step 7. 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.
Visual InspectionS7RS0B7224009
Check visually the following parts and systems.
DTC B1502: Inside Air Temperature Sensor and/or Its Circuit MalfunctionS7RS0B7224010
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
NOTE
When DTC B1503, B1513 and B1514 are indicated together, it is possible that “ORN” wire circuit open.
 
Inspection item Correction
• Refrigerant ---- leakage and amount
• A/C pipe or hose ---- disconnection, looseness and deterioration
• A/C compressor drive belt ---- looseness and damage Refer to “Compressor Drive Belt Inspection and 
Adjustment”.
• Battery ---- fluid level and corrosion of terminal
• Connectors of electric wire harn ess ---- disconnection and friction
• Fuses ---- burning
• Parts ---- installation and damage
• Other parts that can be checked visually
5V
PNK/BLK
ORN G52-6
G52-3
2
1
3
7812910
65 431516 14 13 12 11
G52
789101920121112
65 431718 16 15 14 13
G51
I5RS0A722010-01
1. HVAC control module
2. Inside air temperature sensor 3. To other sensors
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 YesNo
1 Inside air temperature sensor signal circuit check
1) Disconnect inside air temperature sensor connector.
2) Check for proper connection to inside air temperature 
sensor at “PNK/BLK” and “ORN” wire terminals.
3) If OK, measure voltage between “PNK/BLK” wire  terminal of inside air temp erature sensor connector and 
vehicle body ground with ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 2.  
         
        
        
     
        
        Page 998 of 1496

Downloaded from www.Manualslib.com manuals search engine 7B-50 Air Conditioning System: Automatic Type
DTC B1503: A/C Evaporator Air Temperature Sensor and/or Its Circuit MalfunctionS7RS0B7224011
Wiring Diagram2
Inside air temperature sensor signal 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 “G52-6” and “G52-3” terminals.
3) If OK, measure resistance between “PNK/BLK” wire  terminal of inside air temp erature sensor connector and 
“G52-6” terminal of HVAC control module connector.
Is resistance below 5 
Ω? Go to Step 3. “PNK/BLK” wire open or 
high resistance circuit.
3 Inside air temperature sensor signal circuit check
1) Measure resistance between “PNK/BLK” wire terminal of 
inside air temperature sensor connector and vehicle 
body ground.
Is resistance infinity? Go to Step 4.
“PNK/BLK” wire shorted 
to ground circuit.
4 Inside air temperature sensor signal circuit check
1) Measure voltage between “PNK/BLK” wire terminal of 
inside air temperature sensor connector and vehicle 
body ground with ignition switch turned ON.
Is voltage 0 V? Go to Step 5.
“PNK/BLK” wire shorted 
to other circuit.
5 Inside air temperature sensor ground circuit check
1) Connect HVAC control module connector with ignition 
switch turned OFF.
2) Measure resistance between “ORN” wire terminal of  inside air temperature sensor connector and vehicle 
body ground.
Is resistance below 5 
Ω? Go to Step 7. Go to Step 6.
6 Inside air temperature sensor ground circuit check
1) Measure resistance between “G52-3” terminal of HVAC 
control module connector and vehicle body ground.
Is resistance below 5 
Ω? “ORN” wire open or high 
resistance circuit.
HVAC control module 
faulty.
7 Inside air temperature sensor check
1) Check inside air temperature sensor referring to “Inside 
Air Temperature Sensor Inspection”.
Is it in good condition? HVAC control module 
faulty.
Inside air temperature 
sensor faulty.
Step Action Yes No
5V
WHT/BLK
ORN G52-4
G52-3
2
1
3
7812910
65 431516 14 13 12 11
G52
789101920121112
65 431718 16 15 14 13
G51
I5RS0A722011-01
1. HVAC control module
2. Evaporator temperature sensor 3. To other sensors  
         
        
        
     
        
        Page 999 of 1496

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-51
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
NOTE
When DTC B1502, B1513 and B1514 are indicated together, it is possible that “ORN” wire circuit open.
 
DTC Detecting ConditionTrouble 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 YesNo
1 Evaporator temperature sensor signal circuit check
1) Disconnect evaporator temperature sensor connector.
2) Check for proper connection  to evaporator temperature 
sensor at “WHT/BLK” and “ORN” wire terminals.
3) If OK, measure voltage between “WHT/BLK” wire  terminal of evaporator te mperature sensor connector 
and vehicle body ground with ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 2.
2 Evaporator temperature sensor signal 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 “G52-4” and “G52-3” terminals.
3) If OK, measure resistance between “WHT/BLK” wire  terminal of evaporator te mperature sensor connector 
and “G52-4” terminal of HVAC control module connector.
Is resistance below 5 
Ω? Go to Step 3. “WHT/BLK” wire open 
or high resistance 
circuit.
3 Evaporator temperature sensor signal circuit check
1) Measure resistance between “WHT/BLK” wire terminal 
of evaporator temperature sensor connector and vehicle 
body ground.
Is resistance infinity? Go to Step 4. “WHT/BLK” wire 
shorted to ground 
circuit.
4 Evaporator temperature sensor signal circuit check
1) Measure voltage between “WHT/BLK” wire terminal of 
evaporator temperature sens or connector and vehicle 
body ground with ignition switch turned ON.
Is voltage 0 V? Go to Step 5. “WHT/BLK” wire 
shorted to other circuit.
5 Evaporator temperature sensor ground circuit check
1) Connect HVAC control module connector with ignition 
switch turned OFF.
2) Measure resistance between “ORN” wire terminal of  evaporator temperature sens or connector and vehicle 
body ground.
Is resistance below 5 
Ω? Go to Step 7. Go to Step 6.
6 Evaporator temperature sensor ground circuit check
1) Measure resistance between “G52-3” terminal of HVAC 
control module connector and vehicle body ground.
Is resistance below 5 
Ω? “ORN” wire open or high 
resistance circuit.
HVAC control module 
faulty.  
         
        
        
     
        
        Page 1000 of 1496

Downloaded from www.Manualslib.com manuals search engine 7B-52 Air Conditioning System: Automatic Type
DTC B1504: Sunload Sensor and/or Its Circuit MalfunctionS7RS0B7224012
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting7
Evaporator temperature sensor check
1) Check evaporator temperature sensor referring to 
“Evaporator Thermistor (Evaporator Temperature 
Sensor) Inspection”.
Is it in good condition? HVAC control module 
faulty.
Evaporator temperature 
sensor faulty.
Step Action Yes No
5V
PNK G52-2
G52-5
YEL/BLK
2
1
7812910
65 431516 14 13 12 11
G52
789101920121112
65 431718 16 15 14 13
G51
I5RS0A722012-01
1. HVAC control module
2. Sunload sensor
DTC Detecting Condition Trouble Area
Sunload sensor signal voltage is higher than or lower than specified value for 
specified time continuously. • Sunload sensor circuit
• Sunload sensor
• HVAC control module
Step
Action YesNo
1 Sunload sensor power supply circuit check
1) Disconnect sunload sensor connector.
2) Check for proper connection to sunload sensor at “PNK” 
and “YEL/BLK” wire terminals.
3) If OK, measure voltage between “PNK” wire terminal of  sunload sensor connector and vehicle body ground with 
ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 2.
2 Sunload sensor power 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 “G52-2” and “G52-5” terminals.
3) If OK, measure resistance between “PNK” wire terminal  of sunload sensor connector  and “G52-2” terminal of 
HVAC control module connector.
Is resistance below 5 
Ω? Go to Step 3. “PNK” wire open or high 
resistance circuit.
3 Sunload sensor power supply circuit check
1) Measure resistance between “PNK” wire terminal of 
sunload sensor connector and vehicle body ground.
Is resistance infinity? Go to Step 4. “PNK” wire shorted to 
ground circuit.