FULLY AUTOMATIC AIR CONDITIONER
Trouble Diagnosis
by Self-diagnosis Function
(Cont'd)
Step 3 AUTO SW: ON +
I
Step 1
(CW) Tum the temperature (CCW) Turn the temperature
adjustment dial. adjustment dial. I
IGN SW: OFF
AUTO SW: ON *
T
I Step 4 I AUTO SW: ON *
4 (CW) Turn the temperature (CCW) Turn the temperature
adjustment dial. adjustment dial. I
Step 2 IGN SW: OFF
AUTO SW: ON *
I
CW: Clockwise I CCW: Counterclockwise
Step 5 Detected temperature d~splay for each sensor IGN SW: OFF AUTO SW: ON
C : Each switch indicator lamp HAK0725D
SELF-DIAGNOSIS DISPLAY ITEM
Step 1 - Display segments and indicator lamp check
Check the controller switch indicator lamp and display segments.
Normal: The switch indicator lamp and display segments are illu-
minated.
Abnormal: Malfunctioning area will not be illuminated.
lllum~nated when a short- (T"e last digir ") circuit is detected.
the display code
the corresponding codes
Step 2 - Each sensor check
Display shows "2 in the step 2 mode, and then shows the judge-
ment result.
Check the data of each sensor inputted into the automatic ampli-
fier.
Normal: Display shows
"20.
Abnormal: The last digit of the display code flashes for a malfunc-
tioning sensor. At this time, if a short-circuit
is detected,
"AUTO is displayed. Furthermore, when there are more
than one malfunctioning sensor, the corresponding dis-
play codes flash twice starting with the smaller code.
The sunload sensor will judge an abnormality when there is
insufficient lighting (less than 5,000 lx) such as while being
placed indoor or during the evening.
FULLY AUTOMATIC AIR CONDITIONER
Trouble Diagnosis by Self-diagnosis Function
(Cont'd)
Display code for malfunctioning sensor and identifying condition for automatic amplifier
I
The last digit of
Abnormal flashes for is detected.
Display code
21
22
24
25
a malfunctioning ( actuator terminal. I
When more than one
actuator terminal
are malfunctron~ng.
Ihe corresponding codes
flash twice starting
with the smaller code.
Sensor
Ambient sensor in-vehicle sensor
intake air temperature sensor
Sunload
sensor
Flashes twice
HAK0727C
Actuator display code
Identifying condition for automatic amplifier
Step 3 - Each actuator check and reset
Open circuit
Less than
41 .9"C
Less than -4 1 .g°C
Less than -4 1 .9"C
Less than 4 1.8 W/m2 (36.0 kcallm2. h)
Display shows "3" for approx. 1 second in the step 3 mode, and BB
then shows the judgement result.
Transmit an output signal to the intake door actuator, mode door
actuator, and air
mix door actuator; and check each actuator.
Furthermore, the actuator can be reset by pressing the front DEF
switch at this
time.
Normal: Display shows "30". I28
Abnormal: The display code flashes for a malfunctioning actuator.
At this time, if a short-circuit is detected, "AUTO is dis-
played. Furthermore, when there are more than one
malfunctioning sensor, the corresponding display codes
flash twice starting with the smaller code.
During reset: Display flashes
"30" and front DEF switch. (Approx.
P
EL
10 seconds)
Short-circuit
More than 100°C GI
More than 100°C
More than 100°C EG
More than 1729 W/m2 (1 487 kcal/m2.h)
Faulty harness display
SD
Display code
Actuator
Actuator
Terminal No. (actuator side)
Terminal
No. (automatic
amplifier side)
Open or short-circuit failure
display
31.0 - 32.5
Air mix door
': "AUTO" is displayed for a short-circuit.
33.0 - 34.5
Mode door
Air mix door actuator
35.0 - 36.5
Intake door
1
15
31.0
Mode door actuator
2
16
31.5
1
22
33.0
Intake door actuator
1
24
35.0
5
17
32.0 2
30
33.5
6
18
32.5 2
32
35.5
5
29
34.0
6
23
34.5
5
31
36.0 6
36
36.5
FULLY AUTOMATIC AIR CONDITIONER
Trouble Diagnosis
by Self-diagnosis Function -
When '32.5" 1s d~splayed d~rlng self-diagnos~s step 3 I I I (Cont'd)
Au;omafc amplifier
Actuator driver
powe: supply
Air mix driver
1
Air mix driver 2
Air mix driver 3
Air mix driver 4
1 1 Air mix door actuator 1
circuit
I I'
When a open-circuit failure is displayed for all four terminals of
each actuator, there is a possibility of a disconnected
connector, or broken harness of the actuator driver power
SOU rce.
The self-diagnosis cannot detect short-circuit between actua-
tor driver signals, but the actuators will vibrate when actuated.
Step 4 - Each output device check
Display shows "41" in the step 4 mode. When the DEF switch is
pushed it switches from
42-343+44+45-+46-,41. As indicated in
the following table, the automatic amplifier forcefully outputs to
each actuator, blower fan motor, and compressor in response
to
the display code. Confirm and check each output operation status
by observing, listening to the operating sound, placing hand at the
air outlet, or using other methods.
The operation status of each actuator, blower fan motor, and
1
compressor cannot be confirmed on the display.
Display code for output device and status
Display code
Output device / 11 1 42 1 43 I I I
Mode door
Intake door
Air mix door
Blower fan motor
Compressor
Air purifier (only when connected) VENT I B/L FOOT
Ambient
Recirculation
Full cold
BIL
Open 50%
61 0/e 35%
ON
ON
The blower fan motor revolution is controlled by the duty ratio
signal outputted from the automatic amplifier. (For duty ratio,
refer to "Blower Fan Motor System Check" on page
HA-15.)
Step 5 - Detected temperature display for each sensor
Display shows "5" in the step 5 mode. Every time the DEF switch
is pushed, the detected sensor temperature is displayed in
0.5"C
increments.
D/F
Ambient
Recirculation
Full cold
OFF
OFF
f' 7 Sensor display switches every tlme 2 )- z -2 - - ' the front DEF rwttch is pressed. C
X In al - - t 0 - D
A1 E ? < -
DEF
Ambient 20% ambient
Open
50% Full hot
61Yo 75%
ON
ON
Full hot
1 00% 61 %
ON
ON OFF
OFF ON
ON
FULLY AUTOMATIC AIR CONDITIONER
Magnet Clutch System Check
MAGNET CLUTCH
Disconnect the compressor connector. Apply approx. 12V to the compressor to check the magnet clutch
operation.
/;sn
AIR CONDITIONER RELAY QJg
Remove the air conditioner relay. Apply approx. 12V between the air conditioner relay terminals No. 1 and
2. Check the relay operation sound. Ec Check the continuity between terminals No. 3 and 5.
REFRIGERANT CHARGE AMOUNT AT
Connect the manifold gauge to the vehicle side service valve.
Check that the lower pressure side (gauge pressure) is more than approx. 0.1 8 MPa (1.8 kg/cm2.G). BR
ECM
Start the engine, and short-circuit the ECM terminal No. 14 to the ground. Check the magnet clutch operation.
INTAKE AIR TEMPERATURE SENSOR
Start the engine, and short-circuit the intake air temperature sensor terminal No. 1 to the ground. Check the Rs
maanet clutch o~eration.
Blower Fan Motor System Check
BLOWER FAN MOTOR
Disconnect the blower fan motor connector. Short-circuit the blower fan motor terminals No. 2 and 5 to El!, (
the ground. Apply approx. 12V to the terminal No. 6, and check the motor operation.
Connect the blower fan motor connector. Turn the ignition switch to the ON position, and change the fan sD
switch from 1st to 4th. Check the blower fan motor terminal No. 5 with an oscilloscope. When the termi-
nal No.
5 is normal according to the following table and the fan airflow does not change, this indicates a
faulty blower fan motor.
When the terminal No.
5 results differ from the following table and the fan airflow does not change, this
indicates either a faulty harness between the blower fan motor and automatic amplifier, or a faulty auto-
matic amplifier.
FULLY AUTOMATIC AIR CONDITIONER
Symptom
Trouble Diagnosis for Each Symptom
No airflow
Airflow does not change. Operation check
Check blower fan motor operation. (Refer to "Blower Fan Motor Sys-
tem Check".)
The above is normal.
I Automatic amolifier 1 Faultv automatic amplifier
Faulty attachment of air mix door
rod, or air mix door lever
Faulty air mix door system
ElG
(damage, lock, etc.)
Malfunctioning unit
Blower fan motor Probable cause
Faulty blower fan motor
Check attachment status of the air
mix door actuator.
Common item (Check and confirm this
item along with the fol-
lowing three items.)
Air mix door
Abnormal display in self-diagnosis
step
3
Check that the air mix door oper-
ates when the temperature
adjust-
ment dial is set to
18OC or 32°C.
Faulty sensor (Refer to 'Component a
Parts Inspection".)
Faulty sensor harness
Air
mix door actuator
Air mix door actuator
Abnormal display in self-diagnosis
step 2
Magnet clutch does not operate
Magnet clutch Refer
to 'Magnet Clutch System R8
with AUTO switch, or A/C switch. Check".
I Faulty
air mix door actuator
Faulty air mix door actuator system AT
hamess
(Refer to "Actuator System Check".)
BW
Refer to "Actuator System Check".
@'i?
Sensor
Tem- perature
control mal-
function No
cool airflow
(Flow amount is normal.)
ngeranr
cnarge
amounr.
( Cooler cycle 2 ~erformance. I Refer to 'Performance Test". I
The above is normal. I Automatic amolifier 1 Faulty automatic amplifier I
After warming up, the heater core
inlet and outlet hoses are not warm. 1 Coolant I
Engine coolant failure
Clogged heater hose or heater core
No warm airflow
(Flow
amount is normal.)
The above is normal. Automatic amplifier
1 Faulty automatic amplifier
Blower fan motor speed does not
change even when the fan switch is Blower fan motor
changed. Refer
to "Blower Fan Motor System
Check".
I
When the fan switch is in 4th, Faulty aspirator
smoke is not drawn in from the
in-
Aspirator Clogged
or disconnected aspirator
vehicle sensor inlet. duct
Large
in-vehicle tem-
perature difference in
relation to temperature
setting Check the setting difference
between the set temperature and
control temperature. Error
in temperature difference set-
ting
- The above isnormal.- Automatic amplifier Faulty automatic amplifier
Faulty attachment of mode door
lock, mode door link, or mode door
Check mode door operation. Mode door lever
Faulty mode door system (damage,
lock, etc.)
Faulty mode door actuator
Abnormal display in self-diagnosis Faulty mode door actuator system
step
3 Mode door actuator
harness (Refer to "Actuator System
Check".)
Air
outlet does not switch.
Normal display in self-diagnosis
Mode door actuator
step
3
Refer to "DOOR ACTUATOR
HARNESS", "Actuator System
Check".
The above is normal.
I Automatic amplifier I Faulty automatic amplifier - - I I Faulty attachment of intake door
Check intake door operation. lntake
door lever
Faulty intake door system (damage,
lock, etc.)
~aulG intake door actuator
Faulty intake door actuator system
hamess (Refer to "Actuator System
Check".)
Abnormal
display in self-diagnosis
door step 3 Air inlet does fiot switch.
Normal display in self-diagnosis
lntake door actuator
step
3
Refer to "DOOR ACTUATOR
HARNESS", "Actuator System
Check".
I I The above is normal. I Automatic amplifier I Faulty automatic amplifier
FULLY AUTOMATIC AIR CONDITIONER
ln-vehcle sensor characterlstlc and connector I
Temperature "C HAK0669D
Ambient sensor characteristic and connector
Temperature
"C ELZ0174C
I Sunload sensor characteristic and connector
I Sunload kW/m2 (kcaVm2 h) HAK0666C
cake alr temperature sensor characlerlstrc and connector
Temperature
'C ~~~0667~1
Component Parts Inspection
IN-VEHICLE SENSOR
Disconnect the in-vehicle sensor connector. Check the resistance
between the sensor connector terminals No.
1 and 2.
AMBIENT SENSOR
Disconnect ambient sensor connector. Check the resistance
between the sensor connector terminals No.
1 and 2.
SUNLOAD SENSOR
Disconnect the sunload sensor connector.
Turn the ignition switch
ON.
Check that the voltage between the automatic amplifier con-
nector (vehicle side) terminal No.
34 and body ground, is
approx.
4.6V.
When normal, proceed to step
5.
When abnormal, the automatic amplifier is faulty. Or, the har-
ness between the automatic amplifier and
sunload sensor is
faulty. Turn the ignition switch
OFF.
Connect the sunload sensor connector.
Turn the ignition switch
ON.
Check the voltage between the automatic amplifier connector
(vehicle side) terminal
No. 34 and body ground.
When indoors, check the voltage by applying a light of approx.
60W. (Check the voltage with the light placed close to and
away from the sensor.)
The
sunload during a sunny day is equivalent to approx.
767
W/m2 (660 kcal/m2- h).
INTAKE AIR TEMPERATURE SENSOR
Disconnect the intake air temperature sensor connector. Check the
resistance between the sensor connector terminals No.
1 and 2.
THERMAL TRANSMITER
Refer to EL section ("Component Parts Inspection", "COMBINA-
TION
METER").
HA-I 8
AUTO LIGHT SYSTEM
Component
Parts Location Inside the meter
-4 Auto light control unit
Auto Light Control Unit InputlOutput Signal
Specifications
Terminal No. Measuring
condition
Operation or condition
I
Signal name Specification
Ignition switch
I Light is applied to the I Approx. 12V
liaht sensor.
Tail lamp relay control
signal
Speedometer is in operation. (Vehicle speed is
approximately 40
kmlh.)
Lighting switch: AUTO
Vehicle speed signal (2 pulses)
Light is applied to the
liaht
sensor.
I
4
Light is not applied to
the light sensor.
Approx. OV
Approx.
OV
Navigation screen
dimming signal Liahtina
switch: 1 ST
- I I
I
Light is not applied to
the light sensor.
ignition power supply Approx. 12V
I - I
I Light
is applied to the I Approx. 12V
liaht sensor. Approx. 12V
Headlamp
relay con-
trol signal Lighting
switch: AUTO
Lighting switch AUTO
signal Lighting switch
ACC -
Light is not applied to
the light sensor.
Ground Approx.
OV
OFF
AUTO Approx. 12V
Approx. OV
Driver door switch sig-
n
al
ACC Approx.
OV
Approx.
OV
Approx. 12V
-
ACC power supply Driver
door switch
ACC ON
(Open)
OFF (Closed)
- I Approx. 12V
COMBINATION METER
Trouble
Diagnoses
DIAGNOSTIC PROCEDURE
I YES
Meter control unit is faulty.
Meter battery or ignition power supply is faulty.
DO
warning
lamps
on
the
meter light
up?
. No .
at the low fuel warning lamp check? The bulb
is faulty.
t
Meter control unit is faulty. I
Does the liquid crystal display operate properly at the segment check? NO
Check the attaching screw for the ' NG *F3epair malfunct~oning part and
the meter circuit check? meter that
does not operate properly. * conduct the meter circuit check again.
OK
Meter control unit is faulty.
YES
DIAGNOSIS RESULT 1
4
Symptom I Check item I Malfunctioning item
Go
to "DIAGNOSIS RESULT
1".
Low fuel warning lamp does not operate
properly. Go to
"DIAGNOSIS RESULT
2".
Any of tachometer, fuel gauge, and water
temperature gauge does not operate prop-
erly.
More than one meter out of tachometer, fuel
gauge, and water temperature gauge do not
operate properly.
Speedometer and
odohrip meter do not
operate properly. Sensor
or harness for the meter that does
Sensor circuit for the meter (warning lamp)
1 1: 1 not operate properiy
1 that does not operate properly
~ Meter control unit
Meter control unit
DIAGNOSIS RESULT 2
Symptom
Any of speedometer, tachometer, fuel gauge,
and water temperature gauge does not oper-
ate properly. Vehicle
speed sensor or harness
Meter control unit
-
Vehicle speed input signal (with TCS)
Check item
I Malfunctioning item
NG
OK
Perform "VEHICLE SPEED INPUT SIGNAL
DIAGNO-
SIS"
on the next page. (without TCS)
More than one meter out of speedometer,
tachometer, fuel gauge, and water tempera-
ture gauge
do not operate properly. Resistance
of the meter that does not
operate properly
Meter control unit
NG
OK
- -
Meter that does not operate properly
Meter control unit