
Downloaded from www.Manualslib.com manuals search engine 7B-64 Air Conditioning System: Automatic Type
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

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-67
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
65 431516 14 13 12 11
G52
789101920121112
65 431718 16 15 14 13
G51
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”

Downloaded from www.Manualslib.com manuals search engine 7B-68 Air Conditioning System: Automatic Type
G51-8 BLU/REDBlower motor control
voltage feedback 10 – 14 V Ignition switch turned ON, blower speed selector OFF
About 8.5 V Ignition switch turned ON, blower speed selector 1st
position
About 6.5 V Ignition switch turned ON, blower speed selector 2nd
position
About 5.5 V Ignition switch turned ON, blower speed selector 3rd
position
About 4.0 V Ignition switch turned ON, blower speed selector 4th
position
About 3.0 V Ignition switch turned ON, blower speed selector 5th
position
About 2.0 V Ignition switch turned ON, blower speed selector 6th
position
About 1.0 V Ignition switch turned ON, blower speed selector 7th
position
Below 1.0 V Ignition switch turned ON, blower speed selector HIGH
position
G51-9 GRY Blower motor controller 0 – 1 V
Ignition switch turned ON, blower speed selector OFF
position
2 – 3 V Ignition switch turned ON, blower speed selector
between 1st and HIGH position
G51-10 BLK/RED Rear defogger indicator 0 – 1 V Ignition switch turned ON, rear defogger switch OFF
10 – 14 V Ignition switch turned ON, rear defogger switch ON
G51-11 RED/YEL Illumination switch 0 – 1 V Ignition switch turned ON, lighting switch OFF position
10 – 14 V Ignition switch turned ON, lighting switch ON position
G51-12 BLK/YEL Illumination ground 0 – 1 V Full-time
G51-13 — — — —
G51-14 — — — —
G51-15 RED Air intake actuator
(RECIRCULATION AIR) 0 – 1 VIgnition switch turned ON, air intake selector is
recirculation air mode or air intake actuator is working
in operation to recirculation air position or fresh air
position.
10 – 14 V Ignition switch turned ON, ai
r intake selector is fresh
air mode (air intake actuator fresh air position).
G51-16 GRN/RED Air intake actuator
(MIX AIR) 10 – 14 V
Ignition switch turned ON, air intake actuator is
recirculation air or fresh air position.
0 – 1 V Ignition switch turned ON, air intake actuator is mix air
position or air intake actuator is working in operation to
recirculation air position or fresh air position.
G51-17 GRN Air intake actuator
(FRESH AIR) 0 – 1 V
Ignition switch turned ON, ai
r intake selector is fresh
air mode or air intake actuator is working in operation
to recirculation air position or fresh air position.
10 – 14 V Ignition switch turned ON, air intake selector is
recirculation air mode (air intake actuator recirculation
air position).
G51-18 GRN/WHT A/C switch signal Refer to “Inspe ction of BCM and its Circuits in Section 10B”
G51-19 BLU/WHT Electric load signal for
blower motor 10 – 14 V
Ignition switch turned ON, blower speed selector OFF
or between 1st and 5th position
0 – 2 V Ignition switch turned ON, blower speed selector
between 6th and HIGH position
G51-20 BRN Rear defogger switch 0 – 1 V
Ignition switch turned ON, rear defogger switch ON
(rear defogger switch is kept in push) position
4 – 6 V Ignition switch turned ON, rear defogger switch OFF
position
Terminal Wire Color Circuit
Normal
Vo l ta g e Condition

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-69
Terminal Wire Color CircuitNormal
Vo l ta g e Condition
G52-1 WHT Output of 5 V power
source for air flow control
actuator position sensor
and temperature control
actuator position sensor 4 – 6 V Ignition switch turned ON
G52-2 PNK Output of 5 V power
source for sunload sensor 4 – 6 V Ignition switch turned ON
G52-3 ORN Ground for sensors Below 0.3 V Ignition switch turned ON
G52-4 WHT/BLK Evaporator temperature
sensor signal 3.45 – 3.65 V
Ignition switch turned ON, evaporator temperature 0
°
C (32 °F)
2.55 – 2.85 V Ignition switch turned ON, evaporator temperature
15
°C (59 ° F)
1.7 – 2.1 V Ignition switch turned ON, evaporator temperature
30
°C (86 ° F)
G52-5 YEL/BLK Sunload sensor signal
G52-6 PNK/BLK Inside air temperature
sensor signal About 2.0 V
Ignition switch turned ON, room temperature 25
°C
(77 °F)
About 2.8 V Ignition switch turned ON, room temperature 0
°C
(32 °F)
G52-7 — — — —
G52-8 RED/BLK Electric power source 10 – 14 V Ignition switch turned ON
G52-9 — — — —
G52-10 — — — —
G52-11 BLK/ORN Ground for HVAC control
module Below 0.3 V Ignition
switch turned ON
G52-12 — — — —
G52-13 YEL Temperature control
actuator position sensor
signal About 4.0 V
Ignition switch turned ON, temperature selector MAX
COOL position
About 2.0 V Ignition switch turned ON, temperature selector MAX
HOT position
G52-14 WHT/BLU Air flow control actuator
position sensor signal About 4.0 V
Ignition switch turned ON
, air flow selector VENT
position
About 1.6 V Ignition switch ON, air flow selector DEF position
G52-15 — — — —
G52-16 WHT/RED Electric power source for
back-up 10 – 14 V Full-time

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-71
ECM Voltage Values Table for Relation of A/C Control
Repair Instructions
Operation Procedure for Refrigerant ChargeS7RS0B7226001
Refer to “Operation Procedure for Refrigerant Charge”.Terminal Wire Color Circuit Normal Value Condition
C37-14 GRY/RED Output of 5 V power
source 4.5 – 5.5 V Ignition switch turned ON
C37-15 BLK Ground for ECM Below 0.3 V Ignition switch turned ON
C37-24 LT GRN Engine coolant temp.
(ETC) sensor signal 3.3 – 3.8 V Ignition switch turned ON, ECT at 0
°C (32 ° F)
1.38 – 1.72 V Ignition switch turned ON, ECT at 50 °C (122 °F)
C37-30 BLK Ground for ECM Below 0.3 V Ignition switch turned ON
C37-55 ORN Ground for sensors Below 0.3 V Ignition switch turned ON
C37-58 BLK/ORN Ground for ECM Below 0.3 V Ignition switch turned ON E23-1 BLK/RED Main power supply 10 – 14 V Ignition switch turned ON
E23-3 RED CAN (high)
communication line
(active high signal)
for BCM and
combination meterRefer to “DTC P2101: Throttle Actu
ator Control Motor Circuit Range /
Performance in Section 1A”
E23-16 BLK/RED Main power supply 10 – 14 V Ignition switch turned ON
E23-18 WHT CAN (low)
communication line
(active low signal) for
BCM and
combination meterRefer to “DTC P2101: Throttle Actu
ator Control Motor Circuit Range /
Performance in Section 1A”
E23-19 BLU/WHT Electric load signal
for blower motor 10 – 14 V
Ignition switch turned ON, blower speed selector
OFF or between 1st and 5th position
0 – 1 V Ignition switch turned ON, blower speed selector
between 6th and HIGH position
E23-46 LT GRN Radiator fan relay
No.1 output 10 – 14 V
Ignition switch turned ON, engine coolant temp.:
below 95
°C (203 ° F), or A/C refrigerant pressure:
below 600 kPa (87 psi).
0 – 2 V Ignition switch turned ON, engine coolant temp.:
97.5
°C (207.5 °F) or higher, or A/C refrigerant
pressure: 1100 kPa (159.5 psi) or higher.
E23-47 GRY A/C compressor relay
output 10 – 14 V Engine running, A/C request signal high input
0 – 1 V Engine running, A/C request signal low input
E23-48 GRN Radiator fan relay
No.2 and No.3 output 10 – 14 V
Ignition switch turned ON, engine coolant temp.:
below 100
°C (212 °F), or A/C refrigerant
pressure: below 1200 kPa (174 psi).
0 – 2 V Ignition switch turned ON, engine coolant temp.:
102.5
°C (216.5 ° F) or higher, or A/C refrigerant
pressure: 1500 kPa (217.5 psi) or higher.
E23-55 RED A/C refrigerant
pressure sensor
signal 1.46 – 1.71 V
Engine running, A/C refrigerant pressure at 0.8
MPa (8.0 kg/cm
2) (A/C refrigerant pressure
measured by manifold gauge)
2.55 – 2.80 V Engine running, A/C refrigerant pressure at 1.6
MPa (16.0 kg/cm
2) (A/C refrigerant pressure
measured by manifold gauge)
E23-60 BRN/WHT Main power supply
relay output 10 – 14 V Ignition switch turned OFF
0 – 2 V Ignition switch turned ON

Downloaded from www.Manualslib.com manuals search engine Air Conditioning System: Automatic Type 7B-75
6) Connect connector to air flow control actuator.
7) Set air flow selector of HVAC control module to VENT position with ignition switch ON, and make
sure if the position of act uator lever is VENT position
(8).
8) Turn ignition switch OFF, and then disconnect connector from air flow control actuator.
9) Measure resistance between terminal “3” and “5”.
Air flow control actuator resistance between
terminal “3” and “5” (VENT position)
Approximately 2.0 k Ω at 25 °C (77 °F)
If check result is not satisfactory, replace the actuator
with new one.
Air Intake Control Actuator Removal and
Installation
S7RS0B7226008
Refer to “Air Intake Control Actuator Removal and
Installation in Section 7A”.
Air Intake Control Actuator InspectionS7RS0B7226009
Check air intake contro l actuator as follows:
1) Using service wire, connect battery positive terminal
to terminal “7” and battery negative terminal to
terminal “1”. And, check if air intake selector link
operates smoothly and it stops at “REC” position (A).
2) Using service wire, connect battery positive terminal
to terminal “7” and battery negative terminal to
terminal “5”. And, check if air intake selector link
operates smoothly and it stops at “MIX” position (B).
3) For auto A/C model, using service wire, connect battery positive terminal to terminal “7” and battery
negative terminal to “3” terminal. And, check air
intake selector link operates smoothly and it stops at
“FRE” position (C).
If malfunction is found, replace air intake control
actuator.
[A]: LH steering vehicl e [B]: RH steering vehicle
[A]
[B]
8
8765 4 3 21
I5RS0C722005-02
A
C
B“a”
“a”“a”
-
+
A
C
B “1” “3” “5” “7”
“1”
“3”
“5”
“7”
120
°
120° 120
°
I7RS0A722002-01

Downloaded from www.Manualslib.com manuals search engine 7B-76 Air Conditioning System: Automatic Type
Actuator Linkage InspectionS7RS0B7226010
• Check if each actuator linkage operates smoothly.
• Check actuator rod for bend.
• Check each actuator linkage for breakage.
• Make sure if there is not any obstruction in operating range of actuator linkage.
If any malfunction is found, repair or replace faulty
part(s).
Blower Motor Controller Removal and
Installation
S7RS0B7226011
Refer to “Blower Motor Resistor Removal and
Installation in Section 7A”.
Blower Motor Controller InspectionS7RS0B7226012
1) Check internal circuit of controller for resistance as follows.
a) Measure resistance between “1” terminal and “2” terminal of blower motor controller.
Blower motor cont roller resistance
“1” – “2”: approximately 10 k Ω at 25 °C (77 °F)
If resistance does not meet above specification,
replace blower motor controller.
b) Using ohmmeter, connect its positive terminal to “3” terminal of blower motor controller and
negative terminal to “1” terminal of blower motor
controller and check that there is no continuity.
2) Check controller for operation as follows. a) Using service wire, connect battery positive terminal to “3” terminal of blower motor controller
and battery negative terminal to “1” terminal of
blower motor controller.
b) Using bulb (3.4 W) (5) and service wire, connect battery positive terminal to “3” terminal of blower
motor controller as shown figure.
c) Arrange 3 new 1.5 V batteries (6) in series (check that total voltage is 4.5 – 5.0 V) and
connect its positive term inal to “2” terminal of
blower motor controller and negative terminal to
“1” terminal of blower motor controller.
Then, check that bulb lights. If bulb does not light
under the above conditions, replace blower
motor controller.
3
1
2
4
2
1
3
4
5
6I5RS0A722026-01

Downloaded from www.Manualslib.com manuals search engine Air Bag System: 8B-3
• Never attempt disassembly of the air bag (inflator) modules.
• If any abnormality is found, be sure to replace it with
new one as an assembly.
• When an abnormality is noted as existing in the live (undeployed) air bag (inflator) module, be sure to
deploy it before discarding it.
• When grease, cleaning agent, oil, water, etc., got on the air bag (inflator) modules (driver, passenger, side
of both sides and curtain of both sides), wipe it off
immediately with a dry cloth.
• If air bag (inflator) module was dropped from a height of 90 cm (3 ft) or more, it should be replaced with a
new one as an assembly.
WARNING!
• For handling and storage of a live air bag (inflator) module, select a place where the
ambient temperature below 65 °C (150 ° F),
without high humidity and away from
electric noise.
• When carrying a live air bag (inflator) module, make sure the bag opening is
pointed away from you. In case of an
accidental deployment, the bag will then
deploy with minimal chance of injury.
Never carry the air bag (inflator) module by
the wires or connector on the underside of
the module.
Otherwise, personal injury may result.
WARNING!
When placing a live air bag (inflator) module
on bench or other surface, always face the
bag up, away from the surface. As the live
passenger air bag (inflator) module must be
placed with its bag (trim cover) facing up,
place it on the workbench with a slit (1) or
use the workbench vise (2) to hold it securely
at its lower mounting bracket (3).
It is also prohibited to place anything on top
of the trim cover and stack air bag (inflator)
modules.
This is necessary so that a free space is
provided to allow the air bag to expand in the
unlikely event of accidental deployment.
Otherwise, personal injury may result.
Live (Inactivated) Seat Belt Pretensioner
Special care is necessary when handling and storing a
live (inactivated) seat belt pretensioners.
Also, when the seat belt pretensioners activate, gas is
generated and the seat belt (1) is retracted into the
retractor assembly (2) quickly.
Note, therefore, that if they activate accidentally, the seat
belt pretensioners and other object(s) around them may
be thrown through the air.
I4RS0A820002-01
1
2
3
I4RS0A820003-02
I3JA01820043-01