Page 486 of 4449

TROUBLE DIAGNOSIS
ATC-57
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
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
Page 487 of 4449
ATC-58
TROUBLE DIAGNOSIS
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
RJIA0228E
Page 488 of 4449
TROUBLE DIAGNOSIS
ATC-59
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
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
Page 489 of 4449

ATC-60
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
AUXILIARY MECHANISM: FOOT POSITION SETTING TRIMMER
Wind distribution ratio in FOOT mode can be set.
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 the mode switch as desired.
AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION
When ignition key is turned from OFF to ON, inlet port can be set to AUTO or manual.
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 the recirculation (REC) and fresh (FRE) switch as desired.
RJIA1971E
SwitchLED status of
REC/FRE
switchSetting status Setting changeover method
RECON Manual REC status is memorized. (Initial setting)
REC SW: ON
OFF AUTO control
FREON Manual FRE status is memorized.
FRE SW: ON
OFF AUTO control (Initial setting)
Page 491 of 4449

ATC-62
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
CHECKING RECIRCULATION
1. Press recirculation (REC) switch one time. Recirculation indica-
tor should illuminate.
2. Press fresh (FRE) switch one time. Fresh indicator should illumi-
nate.
3. Listen for intake door position change (you should hear blower
sound change slightly).
If NG, go to trouble diagnosis procedure for AT C - 7 6 , "
Intake Door
Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual
inspection) and intake door position is at FRESH when the DEF or D/F is selected.
CHECKING TEMPERATURE DECREASE
1. Press temperature (DOWN) switch (driver side) until 18°C
(60°F) is displayed.
2. Check for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for AT C - 9 1 , "
Insufficient
Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature (UP) switch (driver side) until 32°C (90°F) is
displayed.
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for ATC-100, "
Insufficient
Heating" .
If OK, continue the check.
CHECK A/C SWITCH
1. Press AUTO switch and A/C switch.
2. A/C switch indicator will turn ON.
Confirm that the compressor clutch engages (sound or visual
inspection).
If NG, go to trouble diagnosis procedure for AT C - 8 4 , "
Magnet Clutch
Circuit" .
If OK, continue the check.
RJIA1978E
RJIA1976E
RJIA1977E
RJIA1975E
Page 492 of 4449

TROUBLE DIAGNOSIS
ATC-63
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.
Confirm that the compressor clutch engages (sound or visual
inspection). (Discharge air and blower speed will depend on
ambient, in-vehicle, and set temperatures.)
If NG, go to trouble diagnosis procedure for AT C - 6 3 , "
Power Supply
and Ground Circuit for Auto Amp." , then if necessary, trouble diag-
nosis procedure for AT C - 8 4 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go
to malfunction Simulation Tests in GI-27, "
How to Perform Efficient
Diagnosis for an Electrical Incident" and perform tests as outlined to
simulate driving conditions environment. If symptom appears, refer
to AT C - 4 2 , "
SYMPTOM TABLE" and perform applicable trouble diagnosis procedures.
Power Supply and Ground Circuit for Auto Amp.AJS001BF
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
RJIA1979E
*1AT C - 6 4 , "DIAGNOSTIC PROCE-
DURE FOR A/C SYSTEM".*2ATC-61, "
Operational Check".*3AV- 7 8 , "Trouble Diagnosis Chart by
Symptom".
*4AV- 8 4 , "
A/C and AV Switch Does Not
Operate".
RJIA1980E
Page 493 of 4449

ATC-64
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
COMPONENT DESCRIPTION
Unified Meter and A/C amp. (Automatic Amplifier)
The unified meter and A/C amp. has a built-in microcomputer which
processes information sent from various sensors needed for air con-
ditioner operation. The air mix door motor, mode door motor, intake
door motor, blower motor and compressor are then controlled.
The unified meter and A/C amp. is unitized with control mechanisms.
When the various switches and temperature switch are operated,
data is input to the unified meter and A/C amp. from the DISPLAY
UNIT/DISPLAY C/U using CAN communication.
Self-diagnostic functions are also built into unified meter and A/C
amp. to provide quick check of malfunctions in the auto air condi-
tioner system.
Potentio Temperature Control (PTC)
The PTC is built into the A/C and AV switch. It can be set at an inter-
val of 0.5°C (1.0°F) in the 18°C (60°F) to 32°C (90°F) temperature
range by pressing temperature switch. The set temperature is dis-
played.
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
RJIA1965E
RJIA1982E
RJIA1983E
Page 534 of 4449

TROUBLE DIAGNOSIS
ATC-105
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: 2004 November 2004 FX35/FX45
2. CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between ambient sensor harness connector
E34 terminal 2 (W) and unified meter and A/C amp. harness
connector M57 terminal 49 (W/G).
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK AMBIENT SENSOR
Refer to ATC-106, "
Ambient Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 4 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace ambient sensor.
2. Go to self-diagnosis AT C - 5 4 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
4. CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between ambient sensor harness connector
E34 terminal 1 (Y) and unified meter and A/C amp. harness con-
nector M57 terminal 39 (Y).
4. Check continuity between ambient sensor harness connector
E34 terminal 1 (Y) and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 4 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP -2. Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.2 – 49 : Continuity should exist.
RJIA2018E
1 – 39 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA2019E