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ATC-52
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Revision: 2004 November 2004 FX35/FX45
46 L/W Power supply for IGN2 ON - Battery voltage
49 W/G Sensor ground ON - Approx. 0
50 LG Sunload sensor - - -
53 G Blower motor control signal ON Blower speed: 1st step
54 Y/RPower supply for each door
motorON - Battery voltage
57 BR/Y Blower motor ON signal ONA/C switch: ON (Blower motor
operate)Approx. 0
A/C switch: OFF Approx. 5 Te r m i n a l
No.Wire
colorItemIgnition
switchConditionVoltag e
(V)
SJIA0116J
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Self-diagnosis FunctionAJS0014P
DESCRIPTION
The self-diagnostic system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from usual control to the self-diagnostic system is accomplished by
starting the engine (turning the ignition switch ON) and pressing OFF switch for at least 5 seconds. The OFF
switch must be pressed within 10 seconds after starting the engine (ignition switch is turned ON). This system
will be canceled by either pressing AUTO switch or turning the ignition switch OFF. Shifting from one step to
another is accomplished by means of pressing temperature switch (driver side), as required.
Additionally shifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan)
UP switch.
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ATC-54
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FUNCTION CONFIRMATION PROCEDURE
1. SET IN SELF-DIAGNOSTIC MODE
1. Turn ignition switch ON.
2. Set in self-diagnostic mode as follows. Within 10 seconds after starting engine (ignition switch is turned
ON.), press OFF switch for at least 5 seconds.
CAUTION:
If battery voltage drops below 12V during diagnosis STEP-3, actuator speed becomes slower and
as a result, the system may generate an error even when operation is usual. To avoid this, start
engine before performing this diagnosis.
Former STEP-1 (LEDs and display screen are checked) does not exist in this self-diagnosis func-
tion.
>> GO TO 2.
2. STEP-2: SENSOR CIRCUITS ARE CHECKED FOR OPEN OR SHORT CIRCUIT
Does code No. 20 appear on the display?
YES >> GO TO 3.
NO >> GO TO 13.
3. CHECK TO ADVANCE SELF-DIAGNOSIS STEP-3
Press temperature (UP) switch (driver side).
Advance to self
-diagnosis STEP-3?
YES >> GO TO 4.
NO >> Malfunctioning OFF switch or unified meter and A/C amp. Refer to ATC-102, "
Self-diagnosis" .
4. CHECK TO RETURN SELF-DIAGNOSIS STEP-2
Press temperature (DOWN) switch (driver side).
Return to self
-diagnosis STEP-2?
YES >> GO TO 5.
NO >> Replace A/C and AV switch. Temperature switch malfunctions.
5. STEP-3: MODE DOOR AND INTAKE DOOR POSITIONS ARE CHECKED
Press temperature (UP) switch (driver side).
Does code No. 30 appear on the display?
YES >> GO TO 6.
NO >> GO TO 14.
RJIA0219E
RJIA0220E
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6. STEP-4: OPERATION OF EACH DOOR MOTOR IS CHECKED
1. Press temperature (UP) switch (driver side).
2. Press (DEF) switch. Code No. of each door motor test is
indicated on the display.
>> GO TO 7.
7. CHECK ACTUATORS
Refer to the following chart and confirm discharge air flow, air tem-
perature, blower motor voltage and compressor operation.
Checks must be made visually, by listening to any noise, or by touching air outlets with your hand, etc. for
improper operation.
*1: FOOT position during automatic control. Refer to AT C - 6 0 , "
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER" .
OK or NG
OK >> GO TO 8.
NG >>
Air outlet does not change.
Go to Mode Door Motor Circuit. Refer to AT C - 7 0 , "
Mode Door Motor Circuit" .
Intake door does not change.
Go to Intake Door Motor Circuit. Refer to AT C - 7 6 , "
Intake Door Motor Circuit" .
Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to AT C - 7 9 , "
Blower Motor Circuit" .
Magnet clutch does not engage.
Go to Magnet Clutch Circuit. Refer to AT C - 8 4 , "
Magnet Clutch Circuit" .
Discharge air temperature does not change.
Go to Air Mix Door Motor Circuit. Refer to AT C - 7 3 , "
Air Mix Door Motor Circuit" .
RJIA1968E
SJIA0302E
41 42 43 44 45 46
Mode door position VENT B/L 1 B/L 2 FOOT*1 D/F DEF
Intake door position REC REC 20%FRE FRE FRE FRE
Air mix door position FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
Blower fan duty ratio 37% 91% 65% 65% 65% 91%
Compressor ON ON OFF OFF ON ON
Electronic control
valve (ECV) duty
ratio100% 100% 0% 0% 50% 100%
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ATC-56
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8. STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature (UP) switch (driver side).
2. Code No. 51 appears on the display.
>> GO TO 9.
9. CHECK AMBIENT SENSOR
Press (DEF) switch one time. Temperature detected by ambient
sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 10.
NG >> Go to Ambient Sensor Circuit. Refer to ATC-104, "
Ambi-
ent Sensor Circuit" .
10. CHECK IN-VEHICLE SENSOR
Press (DEF) switch a second time. Temperature detected by in-
vehicle sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 11.
NG >> Go to In-vehicle Sensor Circuit. Refer to ATC-107, "
In-
vehicle Sensor Circuit" .
11 . CHECK INTAKE SENSOR
Press (DEF) switch a third time. Temperature detected by intake
sensor is indicated on the display.
NOTE:
If temperature shown on display greatly differs from actual tempera-
ture, check sensor circuit first, then inspect sensor.
OK or NG
OK >> GO TO 12.
NG >> Go to Intake Sensor Circuit. Refer to AT C - 11 3 , "
Intake
Sensor Circuit" .
RJIA0223E
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12. CHECK CAN COMMUNICATION ERROR
1. Press (REC) switch.
2. CAN communication error between unified meter and A/C amp.
and DISPLAY UNIT or DISPLAY C/U is detected.
OK or NG
OK >> 1. Turn ignition switch OFF or AUTO switch ON.
2. INSPECTION END
NG >> Go to CAN communication. Refer to BCS-14, "
CAN
Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .
Unified meter and A/C amp. - DISPLAY UNIT
Unified meter and A/C amp. - DISPLAY C/U
13. CHECK MALFUNCTIONING SENSOR
Refer to the following chart for malfunctioning code No.
(If two or more sensors malfunction, corresponding code Nos. blink respectively twice.)
*1: Perform self-diagnosis STEP-2 under sunshine.
When performing indoors, aim a light (more than 60W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
*2: ATC-104, "
DIAGNOSTIC PROCEDURE FOR AMBIENT SENSOR" .
*3: ATC-108, "
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR" .
*4: AT C - 11 3 , "
DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR" .
*5: AT C - 11 0 , "
DIAGNOSTIC PROCEDURE FOR SUNLOAD SENSOR" .
*6: AT C - 6 6 , "
DIAGNOSTIC PROCEDURE FOR LAN CIRCUIT" .
>> INSPECTION END
RJIA1969E
Code No. Malfunctioning sensor (Including circuits) Reference page
21 / −21 Ambient sensor *2
22 / −22 In-vehicle sensor *3
24 / −24 Intake sensor *4
25 / −25 Sunload sensor *1 *5
26 / −26 Air mix door motor PBR (Driver side)
*6
27 / −27 Air mix door motor PBR (Passenger side)
RJIA0227E
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ATC-58
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Revision: 2004 November 2004 FX35/FX45
14. CHECK MALFUNCTIONING DOOR MOTOR POSITION SWITCH
Mode and/or intake door motor PBR(s) is/are malfunctioning.
(If two or more mode or intake doors are out of order, corresponding code numbers blink respectively twice.)
*1: If mode door motor harness connector is disconnected, the following display pattern will appear.
31→32→33→34→35→36→Return to 31
*2: If intake door motor harness connector is disconnected, the following display pattern will appear.
37→38→39→Return to 37
*3: FOOT position during automatic control. Refer to AT C - 6 0 , "
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER" .
*4:AT C - 7 0 , "
Mode Door Motor Circuit" .
*5:AT C - 7 6 , "
Intake Door Motor Circuit" .
>> INSPECTION END
Code No. *1 *2Mode or intake door position Reference page
31 VENT
Mode door motor *4 32 B/L 1
33 B/L 2
34 FOOT*3
35 D/F
36 DEF
37 FRE
Intake door motor *5 38 20% FRE
39 REC
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AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER
The trimmer compensates for differences in range of ±3°C (±6°F) between temperature setting (displayed dig-
itally) and temperature felt by driver.
Operating procedures for this trimmer are as follows:
1. Begin Self-diagnosis STEP-5 mode. Refer to AT C - 5 3 , "
Self-diagnosis Function" .
2. Press (fan) UP switch to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds.
4. Press temperature switch (driver side) as desired. Temperature will change at a rate of 0.5°C (1.0°F) each
time a switch is pressed.
CAUTION:
A decimal point is not indicated when the display shows “°C”.
When battery cable is disconnected, trimmer operation is canceled. Temperature set becomes that of initial
condition, i.e. 0°C (0°F).
RJIA1970E