2007 INFINITI M35 MOTOR

TROUBLE DIAGNOSIS
ATC-59
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AT C
Revision: 2007 April2007 M35/M45
Checks must be made visually, by listening the sound, or by touching air outlets with hand, etc. for improper
operation.
*1: FOOT position during automatic control. Refer to AT C - 6 4 , "
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 6 , "
Mode Door Motor Circuit" .

Upper ventilator outlet does not change.
Go to Upper Ventilator Door Motor Circuit. Refer to AT C - 7 9 , "
Upper Ventilator Door Motor Cir-
cuit" .

Intake door does not change.
Go to Intake Door Motor Circuit. Refer to AT C - 8 5 , "
Intake Door Motor Circuit" .

Discharge air temperature does not change.
Go to Air Mix Door Motor Circuit. Refer to AT C - 8 2 , "
Air Mix Door Motor Circuit" .

Blower motor operation is malfunctioning.
Go to Blower Motor Circuit. Refer to AT C - 8 8 , "
Blower Motor Circuit" .

Magnet clutch does not engage.
Go to Magnet Clutch Circuit. Refer to AT C - 9 3 , "
Magnet Clutch Circuit" .
8. STEP-5: TEMPERATURE OF EACH SENSOR IS CHECKED
1. Press temperature control (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 the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 10.
NG >> Go to Ambient Sensor Circuit. Refer to AT C - 11 2 , "
Ambi-
ent Sensor Circuit" .
10. CHECK IN-VEHICLE SENSOR
Press (DEF) switch for the second time. Temperature detected
by in-vehicle sensor is indicated on the display.
NOTE:
If the temperature indicated on the display greatly differs from the
actual temperature, check sensor circuit first, and then check sensor.
OK or NG
OK >> GO TO 11.
NG >> Go to In-vehicle Sensor Circuit. Refer to AT C - 11 5 , "
In-
vehicle Sensor Circuit" .
PJIA0151E
PJIA0152E

TROUBLE DIAGNOSIS
ATC-61
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AT C
Revision: 2007 April2007 M35/M45
13. CHECK MALFUNCTIONING SENSOR AND DOOR MOTOR
Refer to the following chart for malfunctioning code No.
(If two or more sensors and door motors malfunction, corresponding code Nos. indicates 1 second each.)
(If two door motors malfunction, corresponding code Nos. indicates 0.5 second each.)
*1: Perform self-diagnosis STEP-2 under sunshine.
When performing indoors, aim a light (more than 60 W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
*2: AT C - 11 2 , "
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR" .
*3: AT C - 11 6 , "
DIAGNOSIS PROCEDURE FOR IN-VEHICLE SENSOR" .
*4: ATC-121, "
DIAGNOSIS PROCEDURE FOR INTAKE SENSOR" .
*5: AT C - 11 8 , "
DIAGNOSIS PROCEDURE FOR SUNLOAD SENSOR" .
*6: AT C - 8 4 , "
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR PBR" .
>> INSPECTION END
Code No. Malfunctioning sensor and door motor (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)
SJIA1781E

ATC-62
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
14. CHECK MALFUNCTIONING DOOR MOTOR POSITION SWITCH
Door motor PBR is malfunctioning.
(If two or more door motors malfunction, corresponding code Nos. indicates 1 second each.)
*1: If mode door motor (driver and passenger side) harness connector is disconnected, the following display
pattern will appear.
31→32→33→34→Return to 31
*2: If upper ventilator door motor harness connector is disconnected, the following display pattern will appear.
35→36→Return to 35
*3: If intake door motor harness connector is disconnected, the following display pattern will appear.
37→38→39→Return to 37
*4: AT C - 7 8 , "
DIAGNOSIS PROCEDURE FOR MODE DOOR MOTOR" .
*5: AT C - 8 1 , "
DIAGNOSIS PROCEDURE FOR UPPER VENTILATOR DOOR MOTOR" .
*6: AT C - 8 7 , "
DIAGNOSIS PROCEDURE FOR INTAKE DOOR MOTOR" .
>> INSPECTION END
Code No. *1 *2 *3Door position Reference page
31 VENT (Driver side)
Mode door motor *4 32 DEF (Driver side)
33 VENT (Passenger side)
34 DEF (Passenger side)
35 UPPER VENT (Open)
Upper ventilator door
motor*5
36 UPPER VENT (Shut)
37 FRE
Intake door motor *6 38 20% FRE
39 REC
SJIA1782E

TROUBLE DIAGNOSIS
ATC-65
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AT C
Revision: 2007 April2007 M35/M45
Operational CheckNJS000GK
The purpose of the operational check is to check if the individual system operates properly.
CHECKING MEMORY FUNCTION
1. Press the temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Press OFF switch.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for AT C - 111 , "
Memory Function" .
If OK, continue the check.
CHECKING BLOWER
1. Press fan (UP:+) switch. Blower should operate on low speed. The fan symbol should have one blade lit.
2. Press fan (UP:+) switch again, and continue checking blower speed and fan symbol until all speeds are
checked.
3. Leave blower on max. speed.
If NG, go to trouble diagnosis procedure for AT C - 8 8 , "
Blower Motor Circuit" .
If OK, continue the check.
CHECKING DISCHARGE AIR (MODE SWITCH AND DEF SWITCH)
1. Press MODE switch and DEF switch.
2. Each position indicator should change shape.
3. Confirm that discharge air comes out according to the air distribution table. Refer to AT C - 3 7 , "
Discharge
Air Flow" .
If NG, go to trouble diagnosis procedure for AT C - 7 6 , "
Mode 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 D/F or DEF is selected.Conditions : Engine running at normal operating temperature
RJIA4035E

ATC-66
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
CHECKING DISCHARGE AIR (UPPER VENT SWITCH)
1. Press temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Press fan (UP:+) switch until Max. speed.
3. Set MODE switch (driver side) to VENT position.
4. Press UPPER VENT switch. AUTO indicator should illuminate.
5. Press temperature control (DOWN) switch (driver side) until 18°C (60°F) is displayed.
6. Confirm that discharger air come out.
7. Press UPPER VENT switch again. AUTO indicator should OFF.
If NG, go to trouble diagnosis procedure for AT C - 7 9 , "
Upper Ventilator Door Motor Circuit" .
If OK, continue the check.
CHECKING INTAKE AIR
1. Press intake switch. Recirculation indicator should illuminate.
2. Press intake switch again. Fresh indicator should illuminate.
3. Listen for intake door position change. (Slight change of blower sound can be heard.)
If NG, go to trouble diagnosis procedure for AT C - 8 5 , "
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 D/F or DEF is selected.
CHECKING TEMPERATURE DECREASE
1. Press temperature control (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 8 , "
Insufficient Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature control (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-108, "
Insufficient Heating" .
If OK, continue the check.
CHECKING 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 - 9 3 , "
Magnet Clutch Circuit" .
If OK, continue the check.
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.

Confirm that 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 7 , "
Power Supply and Ground Circuit for Auto Amp." , then
if necessary, trouble diagnosis procedure for AT C - 9 3 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to Incident Simulation Tests in GI-28,
"How to Perform Efficient Diagnosis for an Electrical Incident" and perform tests as outlined to simulate driv-
ing conditions environment. If symptom appears, refer to AT C - 4 1 , "
SYMPTOM TABLE" and perform applica-
ble trouble diagnosis procedures.

ATC-68
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
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, upper
ventilator door motor, intake door motor, blower motor and compres-
sor are then controlled.
When the various switches and temperature control switch are oper-
ated, data is input to the unified meter and A/C amp. from the AV
control unit / NAVI control unit using CAN communication.
Self-diagnosis 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 multifunction switch. It can be set at an
interval of 0.5°C (1.0°F) in the 18°C (60°F) to 32°C (90°F) tempera-
ture range by pressing temperature control switch. The set tempera-
ture is displayed.
DIAGNOSIS PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
RJIA4032E
RJIA4048E
RJIA4049E

TROUBLE DIAGNOSIS
ATC-71
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AT C
Revision: 2007 April2007 M35/M45
LAN System CircuitNJS000GN
SYMPTOM: Mode door motors, upper ventilator door motor, air mix door motors and intake door motor does
not operate normally.
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT
1. CHECK POWER SUPPLY FOR UNIFIED METER AND A/C AMP.
1. Turn ignition switch ON.
2. Check voltage between unified meter and A/C amp. harness
connector M65 terminal 70 and ground.
OK or NG
OK >> GO TO 2.
NG >> Replace unified meter and A/C amp.
2. CHECK SIGNAL FOR UNIFIED METER AND A/C AMP.
Confirm A/C LAN signal between unified meter and A/C amp. har-
ness connector M65 terminal 69 and ground using an oscilloscope.
OK or NG
OK >> GO TO 3.
NG >> Replace unified meter and A/C amp.
RJIA4052E
70 – Ground : Battery voltage
RJIA4053E
Terminals
Vo l ta g e (+)
(−)
Unified meter and
A/C amp. connectorTerminal No.
M65 69 Ground
RJIA4054E
SJIA1453J

ATC-72
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
3. CHECK POWER SUPPLY FOR EACH DOOR MOTOR
Check voltage between each door motor harness connector terminal
1 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK SIGNAL FOR EACH DOOR MOTOR
Confirm A/C LAN signal between each door motor harness connec-
tor terminal 3 and ground using an oscilloscope.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5. CHECK MOTOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect each door motor connector.
3. Check continuity between each door motor harness connector
terminal 2 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.1 – Ground : Battery voltage
RJIA1988E
Door motorTerminals
Vo l ta g e (+)
(−)
Con-
nectorTerminal
No.
Mode (Driver
side)M252 3
Ground Mode (Pas-
senger side)M255 3
Upper venti-
latorM254 3
Air mix
(Driver side)M253 3
Air mix (Pas-
senger side)M256 3
Intake M257 3
RJIA1989E
SJIA1453J
2 – Ground : Continuity should exist.
RJIA1990E