Signal SUZUKI SWIFT 2007 2.G Service Workshop Manual

Downloaded from www.Manualslib.com manuals search engine 7-ii Table of Contents
Recommended Service Material ....................... 7B-33
Special Tool ...................................................... 7B-33
Automatic Type .................... .................................7B-34
Precautions.........................................................7B-34 A/C System Caution .......................................... 7B-34
Precautions in Diagnosing Trouble ................... 7B-34
Precautions on Servicing A/C System .............. 7B-34
General Description .......... .................................7B-34
Auto A/C System Descript ion ............................ 7B-34
HVAC Control Module Operation Description ... 7B-36
Refrigerant Type Identifica tion .......................... 7B-36
Sub-Cool A/C System Description .................... 7B-36
A/C Operation Description ................................ 7B-36
On-Board Diagnostic System Description ......... 7B-37
Schematic and Routing Diagram ......................7B-37 Major Components of A/C System .................... 7B-37
A/C System Wiring Diagra m ............................. 7B-38
Diagnostic Information and Procedures ..........7B-39 A/C System Symptom Diagnosis ...................... 7B-39
Abnormal Noise Sympto m Diagnosis of A/C
System ............................................................ 7B-42
DTC Check........................................................ 7B-42
DTC Clearance ................................................. 7B-43
DTC Table ......................................................... 7B-44
Fail-Safe Table ................. ................................. 7B-45
Scan Tool Data ................................................. 7B-46
Air Conditioning System Check......................... 7B-47
Visual Inspection ............................................... 7B-49
DTC B1502: Inside Air Temperature Sensor and/or Its Circuit Malfunction .......................... 7B-49
DTC B1503: A/C Evaporator Air Temperature Sensor and/or Its Circuit Malfunction .............. 7B-50
DTC B1504: Sunload Sensor and/or Its Circuit Malfunction ......... ................................. 7B-52
DTC B1511: Temperature Control Actuator (Position Sensor) and/or Its Circuit
Malfunction ...................................................... 7B-53
DTC B1512: Air flow Control Actuator (Position Sensor) and/or Its Circuit
Malfunction ...................................................... 7B-55
DTC B1513: Temperature Control Actuator and/or Its Circuit Malfunction .......................... 7B-57
DTC B1514: Air Flow Co ntrol Actuator and/or
Its Circuit Malfunction ...................................... 7B-60
DTC B1541: HVAC Control Module Back-Up Power Supply Malfunction .............................. 7B-62
DTC B1546: A/C Refrigerant Pressure Malfunction ...................................................... 7B-63
DTC B1551: Serial Communication Circuit Malfunction ...................................................... 7B-63
DTC B1552: Serial Communication Signal Malfunction ...................................................... 7B-64
DTC B1553: CAN Communication Signal Malfunction ...................................................... 7B-65
DTC B1557: Vehicle Speed Sensor Signal Malfunction ...................................................... 7B-65
DTC B1561: Engine Coolant Temperature Sensor Signal Malfunctio n .............................. 7B-66 DTC B1562: Outside Air Temperature Sensor
Signal Malfunction ........................................... 7B-66
DTC B1563: A/C Refr igerant Pressure
Sensor Signal Malfunction .............................. 7B-66
Inspection of HVAC Control Module and Its Circuit .............................................................. 7B-67
A/C System Performance Inspection ................ 7B-70
A/C System Inspection at ECM ......................... 7B-70
Repair Instructions ............ ................................7B-71
Operation Procedure for Refrigerant Charge .... 7B-71
HVAC Unit Components ................................... 7B-72
HVAC Unit Removal and In stallation ................ 7B-73
Temperature Control Actuator Removal and Installation ....................................................... 7B-73
Temperature Control Actuat or Inspection ......... 7B-73
Air Flow Control Actuator Removal and Installation ....................................................... 7B-74
Air Flow Control Actuator Inspection ................. 7B-74
Air Intake Control Actuator Removal and Installation ....................................................... 7B-75
Air Intake Control Actuator Inspection............... 7B-75
Actuator Linkage Inspection .............................. 7B-76
Blower Motor Controller Removal and Installation ....................................................... 7B-76
Blower Motor Controller Inspection ................... 7B-76
HVAC Control Module Removal and Installation ....................................................... 7B-77
Sunload Sensor Removal and Installation ........ 7B-77
Sunload Sensor Inspection ............................... 7B-77
Outside Air Temperature Sensor Removal and Installation ................................................ 7B-77
Outside Air Temperature Sensor Inspection ..... 7B-77
Inside Air Temperature Sensor Removal and Installation ....................................................... 7B-78
Inside Air Temperature Sens or Inspection ........ 7B-78
Condenser Assembly On-Vehicle Inspection .... 7B-78
Condenser Assembly Removal and Installation ....................................................... 7B-78
Receiver/Dryer Removal and Installation .......... 7B-78
Evaporator Inspection ....................................... 7B-78
Evaporator Temperature Sensor Removal and Installation ................................................ 7B-78
Evaporator Temperature Se nsor Inspection ..... 7B-78
Expansion Valve Removal an d Installation ....... 7B-78
Expansion Valve Inspection .............................. 7B-78
A/C Refrigerant Pressure Sensor and Its Circuit Inspection............................................. 7B-78
A/C Refrigerant Pressu re Sensor Removal
and Installation ................................................ 7B-78
Compressor Relay Inspection .
.......................... 7B-78
Compressor Drive Belt Inspection and Adjustment ...................................................... 7B-78
Compressor Drive Belt Removal and Installation ....................................................... 7B-79
Compressor Assembly Removal and Installation ....................................................... 7B-79
Compressor Assembly Components................. 7B-79
Magnet Clutch Removal and Installation........... 7B-79
Magnet Clutch Inspection.................................. 7B-79
Relief Valve Inspection...................................... 7B-79

Downloaded from www.Manualslib.com manuals search engine 7B-4 Air Conditioning System: Manual Type
Sub-Cool A/C System DescriptionS7RS0B7211003
In the sub-cool A/C system (condenser integrated with receiver/dryer), the inside of the condenser is divided into the
condensation part and the sub-cooler part, and the receiver/dryer is located between those. In the receiver/dryer, the
refrigerant is separated into the vapor refrigerant and the liqui d refrigerant. Only the liquid refrigerant is delivered to the
sub-cooler part of the condenser. The refrigerant is supercooled by the sub-cooler part of the condenser.
A/C Operation DescriptionS7RS0B7211004
ECM controls the radiator fan relay and the compressor relay by following signals.
• ON/OFF signal of A/C switch
• A/C refrigerant pressure sensor
• Evaporator thermistor (evaporator temperature sensor)
• ECT sensor
NOTE
The signal of A/C swit ch is fed from BCM to ECM usin g CAN communication system. For CAN
communication system, refer to “CAN Communication System Description in Section 1A”.

I7RS0A721001-01
[A]: Liquid 2. Magnet clutch 6. Expansion valve10. Desiccant
[B]: Vapor 3. Condenser 7. A/C evaporator11. Filter
[C]: Superheated vapor 4. Receiver/dryer (Modulator) 8. Condensation part12. Vapor refrigerant
1. Compressor 5. Refrigerant pressure sensor 9. Sub-cooler part 13. Liquid refrigerant

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Auto A/C Electronic Control Input / Output Table
HVAC Control Module Operation DescriptionS7RS0B7221002
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 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 and sunload sensor.
Using thus obtained target temperature control door
position, it further calculates the target air flow control
door position and controls the ai r flow control actuator so
that the current air flow c ontrol 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)
Refrigerant Type IdentificationS7RS0B7221003
Refer to “Refrigerant Type Identification”.
Sub-Cool A/C System DescriptionS7RS0B7221005
Refer to “Sub-Cool A/C System Description”.
A/C Operation DescriptionS7RS0B7221006
Refer to “A/C Operation Description”.
Sunload sensor
Outside air temperature sensor Evaporator temperature sensor
A/C refrigerant pressure sensor
Temperature selector
MODE (air flow) selector
Blower speed selector
Air intake selector
AUTO switch
A/C switch
Compressor
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
Inside air temperature sensor
VSS
*
I5RS0C722002-02
*: CAN communication

Downloaded from www.Manualslib.com manuals search engine 7B-44 Air Conditioning System: Automatic Type
3) Light over sunload sensor vertically with an incandescent lamp approximately 100 W apart from
about 100 mm (3.94 in.).
NOTE
If sunload sensor is not lighted over with an
incandescent lamp, DTC B1504 is detected
as current DTC even though there is not any
malfunction.

4) Turn ignition switch to ON position.
5) Erase DTC according to instructions 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 clearance, turn ignition switch to OFF position, and then di sconnect SUZUKI scan
tool from DLC.
Not Using SUZUKI Scan Tool 1) Turn ignition switch to ON position.
2) Set temperature selector to 25 °C (77 °F). 3) Push AUTO switch (1) and
MODE (air flow) selector
(2) at the same time to have history DTC displayed.
4) Push MODE (air flow) selector (2) and OFF switch (3) at the same time while history DTC is displayed.
5) Check that “CL” (4) appears on display. “CL” means that DTC has been cleared.
DTC TableS7RS0B7224005
CAUTION!
Be sure to perform “Air Conditioning Sy stem Check” before starting diagnosis.

1
2
3
2
4
I5RS0A722008-01
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
) B1502 21 1 1 Inside air temperature sensor and/or its
circuit malfunction Open
Flashed
22 2 2 Short
) B1503 31 3 3 Evaporator temperature sensor and/or its
circuit malfunction Open
Flashed
32 4 4 Short
) B1504 41 21 — Sunload sensor and/or its circuit
malfunction Open —
42 5 5 Short Flashed
) B1511 61 6 6 Temperature control actuator (position
sensor) and/or its circuit malfunction Open
Flashed
62 7 7 Short
) B1512 71 8 8 Air flow control actuator (position sensor)
and/or its circuit malfunction Open
Flashed
72 9 9 Short
) B1513 63 10 10 Temperature control actuator and/or its circuit malfunction Flashed
) B1514 73 11 11 Air flow control actuator and/or its circuit malfunction Flashed
) B1541 E1 12 — HVAC control module back-up power supply malfunction —
) B1546 d5 22 — A/C refrigerant pressure malfunction —
) B1551 91 13 12
Serial communication circuit malfunction Open
Flashed
92 14 13 Short
) B1552 94 15 14 Serial communication signal malfunction Flashed
) B1553 A4 16 15 CAN communication signal malfunction Flashed
) B1557 b4 19 16 Vehicle speed sensor signal malfunction —
) B1561 54 17 17 Engine coolant temperature sensor signal malfunction Flashed

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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).

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.

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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.

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

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.

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.