ATC-80
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too low. There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
Liquid tank inlet and expan-
sion valve are frosted. Liquid tank inside is slightly
clogged.
Replace liquid tank.
Check lubricant for contami-
nation.
Temperature of expansion valve inlet is extremely low
as compared with areas
near liquid tank.
Expansion valve inlet is frosted.
Temperature difference oc- curs somewhere in high-
pressure side. High-pressure pipe located be-
tween liquid tank and expan-
sion valve is clogged.
Check and repair malfunc-
tioning parts.
Check lubricant for contami- nation.
Expansion valve and liquid
tank are warm or slightly cool
when touched. Low refrigerant charge.
↓
Leaking fittings or compo-
nents.
Check refrigerant for leaks.
Refer to
ATC-138, "
Checking
of Refrigerant Leaks".
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specifica-
tion.
↓
1. Improper expansion
valve adjustment.
2. Malfunctioning expansion
valve.
3. Outlet and inlet may be clogged. Remove foreign particles by
using compressed air.
Replace expansion valve.
Check lubricant for contami-
nation.
An area of the low-pressure
pipe is colder than areas near
the evaporator outlet. Low-pressure pipe is clogged
or crushed. Check and repair malfunc-
tioning parts.
Check lubricant for contami- nation.
Air flow volume is not enough
or is too low. Evaporator is frozen. Check intake sensor circuit.
Refer to AT C - 9 4 , "
Intake
Sensor Circuit".
Replace compressor.
Repair evaporator fins.
Replace evaporator.
Refer to AT C - 6 4 , "
Blower
Motor Circuit".
AC353A
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes be-
comes negative. Air conditioning system does
not function and does not cy-
clically cool the compart-
ment air.
The system constantly func- tions for a certain period of
time after compressor is
stopped and restarted. Refrigerant does not discharge
cyclically.
↓
Moisture is frozen at expan-
sion valve outlet and inlet.
↓
Water is mixed with refrigerant.
Drain water from refrigerant
or replace refrigerant.
Replace liquid tank.
AC354A
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
TROUBLE DIAGNOSISATC-91
< SERVICE INFORMATION >
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After disconnecting in-vehicle sensor connector M46, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace in-vehicle sensor.
Sunload Sensor CircuitINFOID:0000000001328198
COMPONENT DESCRIPTION
Sunload Sensor
The sunload sensor is located on the passenger’s side front
defroster grille. It detects sunload entering through windshield by
means of a photo diode. The sensor converts the sunload into a cur-
rent value which is then input into the unified meter and A/C amp.
SUNLOAD INPUT PROCESS
The unified meter and A/C amp. also includes a processi ng circuit which averages the variations in detected
sunload over a period of time. This prevents drastic swings in the ATC system operation due to small or quick
variations in detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload
detected by the sunload sensor will vary whenever the tr ees obstruct the sunlight. The processing circuit aver-
ages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily
obstructing the sunlight does not cause any change in t he ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize t he change in sunload, and the system will react accord-
ingly.
DIAGNOSIS PROCEDURE FOR SUNLOAD SENSOR
Temperature °C ( °F) Resistance k Ω
− 15 (5) 12.73
− 10 (14) 9.92
− 5 (23) 7.80
0 (32) 6.19
5 (41) 4.95
10 (50) 3.99
15 (59) 3.24
20 (68) 2.65
25 (77) 2.19
30 (86) 1.81
35 (95) 1.51
40 (104) 1.27 45 (113) 1.07
RJIA2025E
RJIA2026E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
ATC-138
< SERVICE INFORMATION >
REFRIGERANT LINES
O-rings are different from low-pressure pipe 1 (high-pressure pipe 2) and low-pressure pipe 2 (high-
pressure pipe 3).
Mark the mounting position of intake sensor bracket prior to removal so that the reinstalled sensor
can be located in the same position.
When recharging refrigerant, check for leaks.
Removal and Installation of Expansion ValveINFOID:0000000001328230
REMOVAL
1. Remove evaporator. Refer to ATC-137, "Removal and Installation of Evaporator".
2. Remove mounting bolts, and then remove expansion valve. CAUTION:
Cap or wrap the joint of evaporator with suitable material
such as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:
Replace O-rings of evaporator with new ones, and then apply compressor oil to it when installing it.
O-rings are different from low-pressure pipe 1 (h igh-pressure pipe 2) and low-pressure pipe 2 (high-
pressure pipe 3).
When recharging refrigerant, check for leaks.
Checking of Refrigerant LeaksINFOID:0000000001328231
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C lubricant
leakage, damage and corrosion. A/C lubricant leakage ma y indicate an area of refrigerant leakage. Allow
extra inspection time in these areas when using either an electrical leak detector or fluorescent dye leak
detector (SST: J-42220).
If dye is observed, c onfirm the leak with an electrical leak detector. It is possible a prior leak was repaired and
not properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electric al leak detector, move the probe along the suspected
leak area at 1 to 2 inches per second and no further than 1/4 inch from the component.
CAUTION:
Moving the electrical leak detector probe slower and closer to the suspected leak area will improve the
chances of finding a leak.
Checking System for Leaks Using the Fluore scent Leak DetectorINFOID:0000000001328232
1. Check A/C system for leaks using the UV lamp and safety goggles (SST: J-42220) in a low sunlight area
(area without windows preferable). Illuminate all co mponents, fittings and lines. The dye will appear as a
bright green/yellow area at the point of leakage. Fluorescent dye observed at the evaporator drain open-
ing indicates an evaporator core assembly (tubes, core or expansion valve) leak.
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or
cloth, with the UV lamp for dye residue.
3. After the leak is repaired, remove any residual dye using dye cleaner (SST: J-43872) to prevent future
misdiagnosis. Low-pressure pipe 1 bracket mounting bolt
: 5.5 N·m (0.56 kg-m, 49 in-lb)
RJIA1864E
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INTEGRATED DISPLAY SYSTEMAV-67
< SERVICE INFORMATION >
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Terminal and Reference Valu e for Display Control UnitINFOID:0000000001328718
Te r m i n a l
(Wire color) ItemSignal
input/
output Condition
Reference value
+– Ignition
switch Operation
1 (W/L) Ground Battery power su pply Input OFF — Battery voltage
2 (W/G) Ground Power supply (Invert-
er)
Output ON — Approx. 9 V
3 (B) Ground Ground — ON — Approx. 0 V
4 (BR/W) Ground Power supply (Signal) Output ON — Approx. 9 V 5 (P) Ground Ground (Inverter) — ON — Approx. 0 V
6 (OR) Ground Reverse signal Input ON Selector lever in R position Approx. 12 V
Selector lever except in R
position
Approx. 0 V
7 (P/L) Ground Ground (Signal) — ON — Approx. 0 V
10 (LG) Ground ACC power supply Input ACC — Battery voltage 12 (W) Ground Ignition signal Input ON — Battery voltage13 (B) Ground Ground — ON — Approx. 0 V
14 (R/L) Ground Illumination signal Input OFF Lighting switch ON Approx. 12 V
Lighting switch OFF Approx. 0 V
16 (G) Ground Vehicle speed signal
(8-pulse) Input ONWhen vehicle speed is ap-
prox. 25 MPH (40 km/h) NOTE:
Maximum voltage may be 5 V
due to specifications (connected
units).
25 (L) — CAN-H — — — —
26 (P) — CAN-L — — — —
28 (PU) Ground Communication
signal (+) Input/
Output ON —
29 — Shield — — — —
30 (LG) Ground Communication
signal (–) Input/
Output ON —
PKIA1935E
SKIB7378E
SKIB7379E
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INTEGRATED DISPLAY SYSTEMAV-73
< SERVICE INFORMATION >
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Self-Diagnosis Mode (DCU)INFOID:0000000001328723
OPERATION PROCEDURE
1. Start the engine.
2. Turn the audio system OFF.
3. While pressing the “4” button, turn the volume control dial clock- wise or counterclockwise for 30 clicks or more. (When the self-
diagnosis mode is started, a short beep will be heard.)
Shifting from current screen to previous screen is performedby pressing “BACK” button.
4. The initial trouble diagnosis screen will be shown, and items “Self Diagnosis (DCU)”, “Confirmation/Adjustment” and “CAN
DIAG SUPPORT MONITOR” will become selective.
5. Perform self-diagnosis by selecting the “Self Diagnosis (DCU)”. Self-diagnosis screen is displayed, and then self-diagnosisstarts.
The bar graph visible below self-diagnosis screen displays progress of the diagnosis.
Mode Description
Self Diagnosis (DCU) Display control unit diagnosis
Analyzes connection between the display control unit and each unit, and
operation of each unit.
Confirmation/
Adjustment Display Diagnosis
Color tone and shading of the display control unit-generated image can be
checked by the display of a color bar and a gray scale.
Vehicle Signals Diagnosis of signals that are input to display control unit can be performed
for Vehicle Speed, IGN, Reverse and Light.
Auto Climate Control Refer to AT C - 4 3 , "
Self-Diagnosis Function".
CAN DIAG SUPPOPT MONITOR The transmitting/receiving of CAN communication can be monitored.
SKIB8743E
SKIB7871E
SKIA4208E
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AV-76
< SERVICE INFORMATION >
INTEGRATED DISPLAY SYSTEM
4. The initial trouble diagnosis screen will be shown, and items“Self Diagnosis (DCU)”, “Confirmation/Adjustment” and “CAN
DIAG SUPPORT MONITOR” will become selective.
5. Select “Confirmation/Adjustment”.
6. Each diagnosis is shown by selecting each screen switch on Confirmation/Adjustment screen.
DISPLAY DIAGNOSIS
Color tone and shading of the display control unit-generat ed image can be checked by the display of a color
bar and a gray scale.
If RGB signal is malfunctioning, the tint of the color bar display is as follows.
VEHICLE SIGNALS
SKIB7871E
SKIB7873E
R (red) signal error : Light blue (Cyan) tint
G (green) signal error : Purple (Magenta) tint
B (blue) signal error : Yellow tint
SKIB7777E
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INTEGRATED DISPLAY SYSTEMAV-77
< SERVICE INFORMATION >
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A comparison check can be made of each actual vehicle signal and
the signals recognized by the display control unit.
NOTE:
In case of confirming light signal, set the following D/N mode to ON/
OFF of lighting switch (normal setting).
OFF: D (Day mode)
ON: N (Night mode)
Unless above setting, light signal (ON/OFF) may not be accurately
displayed.
AUTO CLIMATE CONTROL
Refer to ATC-43, "Self-Diagnosis Function".
CAN Diagnostic Support MonitorINFOID:0000000001328725
OPERATION PROCEDURE
1. Start the engine.
2. Turn the audio system OFF.
3. While pressing the “4” button, turn the volume control dial clock-
wise or counterclockwise for 30 clicks or more. (When the self-
diagnosis mode is started, a short beep will be heard.)
Shifting from current screen to previous screen is performedby pressing “BACK” button.
SKIB7778E
Diagnosis item Display Condition Remarks
Vehicle Speed ON When vehicle speed is more than 0 km/h (0 MPH)
Changes in indication may be delayed.
This is normal.
OFF When vehicle speed is 0 km/h (0 MPH)
— Ignition switch in ACC position
IGN ON Ignition switch ON
—
OFF Ignition switch ACC position
Reverse ON Selector lever in R position
Changes in indication may be delayed.
This is normal.
OFF Selector lever in any position other than R position
— Ignition switch in ACC position
IVCS OFF — This vehicle does not use it.
Light ON Lighting switch ON
—
OFF Lighting switch OFF
SKIB8743E
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AV-82
< SERVICE INFORMATION >
INTEGRATED DISPLAY SYSTEM
4. Check voltage between display control unit harness connectorM75 terminals 4 and 7.
OK or NG
OK >> Replace display.
NG >> Replace display control unit.
5.CHECK DISPLAY CONTROL UNIT PO WER SUPPLY AND GROUND CIRCUIT
1. Check voltage between display control unit harness connector terminals and ground.
2. Turn ignition switch OFF.
3. Disconnect display control unit connector.
4. Check continuity between display control unit harness connector M75 terminal 3 and ground.
OK or NG
OK >> Replace display control unit.
NG >> Repair harness or connector.
Tint Is Strange for the RGB ImageINFOID:0000000001328730
Symptom: Tint of al l RGB images is strange.
1.CHECK HARNESS
1. Turn ignition switch OFF.
2. Disconnect display control unit and display connectors.
3. Check the malfunctioning circuit according to the symptoms.
Light blue (Cyan) tinged screen
Check continuity between display control unit harness connector
(A) M76 terminal 50 and display harness connector (B) M63 termi-
nal 17.
Check continuity between display control unit harness connector
(A) M76 terminal 50 and ground. 4 – 7 : Approx. 9 V
SKIB7842E
Te r m i n a l s
OFF ACC ON
(+)
(–)
Connector Terminal
M75 1
Ground Battery
voltage Battery
voltage Battery
voltage
10 0 V Battery
voltage Battery
voltage
3 – Ground : Continuity should exist.
SKIB7843E
SKIB7844E
50 – 17 : Continuity should exist.
50 – Ground : Continuity should not exist.
SKIB7853E
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