2008 NISSAN LATIO service

TROUBLE DIAGNOSIS
MTC-37
< SERVICE INFORMATION >
C
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MTC
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OK >> GO TO 11.
NG >> Repair harness or connector.
11 .CHECK FAN SWITCH
Check continuity between front air control terminal 9 and 10, 11, 12,
13, 14.
OK or NG
OK >> Replace the front blower motor resistor. Refer to MTC-66, "Removal and Installation".
NG >> Replace front air control. Refer to MTC-58, "
Removal and Installation".
Magnet Clutch Circuit (If Equipped)INFOID:0000000001704305
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - MAGNET CLUTCH
1. Turn ignition switch ON.
2. Turn blower control dial to the desired (1 to 4 speed) position.
3. Press the A/C switch. A/C indicator will turn on.
4. Confirm that the compressor clutch engages (sound or visual inspection).
Can the symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to MTC-30, "
Operational Check".
Does another symptom exist?
YES >> Refer to MTC-22, "How to Perform Trouble Diagnosis for Quick and Accurate Repair".
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK COMPRESSOR BELT TENSION
Check compressor belt tension. Refer to EM-13, "
Checking Drive Belts".
OK or NG
OK >> GO TO 5.
NG >> Adjust or replace A/C compressor belt.
5.CHECK REFRIGERANT PRESSURE
Check refrigerant pressure with manifold gauge connected. Refer to MTC-45, "
Insufficient Cooling".
OK or NG
OK >> GO TO 6.
NG >> Perform trouble diagnosis for unusual pressure. Refer to MTC-45, "
Insufficient Cooling".
6.CHECK MAGNET CLUTCH CIRCUIT
Terminals Condition Continuity
914 Fan control dial: OFF
Ye s 10 Fan control dial: 1-speed
11 Fan control dial: 2-speed
12 Fan control dial: 3-speed
13 Fan control dial: 4-speed
SJIA0732E

MTC-38
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Perform diagnostic procedure for the magnetic clutch. Refer to "DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH".
OK or NG
OK >> If the symptom still exists, perform a complete operational check. Refer to MTC-30, "Operational
Check". If other symptoms exist, refer to MTC-22, "How to Perform Trouble Diagnosis for Quick
and Accurate Repair".
NG >> Repair as necessary.
SYSTEM DESCRIPTION
Thermo control amp. controls A/C compressor operation by intake air temperature and signal from ECM.
The defrost A/C switch controls A/C compressor operation by the BCM when the mode switch is turned to the
(DEF) position.
Low Temperature Protection Control
When intake air temperatures are higher than 4°C (39°F), the com-
pressor turns ON. The compressor turns OFF when intake air tem-
peratures are lower than 2°C (36°F).
DIAGNOSTIC PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage in A/C, defrost/foot, or defrost mode.
1.PERFORM AUTO ACTIVE TEST
Refer to PG-19, "
Auto Active Test".
Does the magnet clutch operate?
YES >> GO TO 5.
NO >> Check 10A fuse (No. 42, located in the IPDM E/R). Refer to PG-22, "
IPDM E/R Terminal
Arrangement".
• If fuse is OK, GO TO 2.
• If fuse is NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
2.CHECK POWER SUPPLY FOR IPDM E/R
Check power supply to 10A fuse (No. 42 located in the IPDM E/R).
SJIA0741E
WJIA2250E
:Battery voltage should exist

TROUBLE DIAGNOSIS
MTC-39
< SERVICE INFORMATION >
C
D
E
F
G
H
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MA
B
MTC
N
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OK or NG
OK >> GO TO 3.
NG >> Check harness for open circuit. Repair or replace if necessary.
3.CHECK POWER SUPPLY FOR A/C COMPRESSOR
1. Disconnect A/C compressor connector.
2. Start the engine.
3. Turn blower control dial and A/C switch ON.
4. Check voltage between A/C compressor harness connector F3
terminal 1 and ground.
OK or NG
OK >> Replace magnet clutch. Refer to MTC-78, "Removal and
Installation of Compressor"
NG >> GO TO 4.
4.CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector.
3. Check continuity between A/C compressor harness connector
F3 (A) terminal 1 and IPDM E/R harness connector E43 (B) ter-
minal 11.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-26, "Removal and
Installation of IPDM E/R"
NG >> Repair harness or connector.
5.CHECK DEFROST A/C SWITCH
1. Start the engine.
2. Turn the mode control dial to (DEF) position.
Does the magnet clutch operate
OK >> GO TO 6.
NG >> GO TO 23.
6.CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
1. Turn ignition switch OFF.
2. Check compressor ON/OFF signal. Refer to MTC-22, "
CONSULT-III Function (BCM)".
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.CHECK CIRCUIT CONTINUITY BETWEEN FRONT AIR CONTROL AND BCM 1 - Ground :Battery voltage
SJIA0743E
1 - 11 :Continuity should exist
WJIA2233E
A/C SW ON : AIR COND SW ON
A/C SW OFF : AIR COND SW OFF

MTC-40
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Disconnect front air control and BCM connector.
3. Check continuity between front air control harness connector
M33 (A) terminal 1and BCM harness connector M18 (B) termi-
nal 27.
OK or NG
OK >> GO TO 8.
NG >> Repair harness or connector.
8.CHECK REFRIGERANT PRESSURE SENSOR
1. Reconnect front air control connector and BCM connector.
2. Check refrigerant pressure sensor. Refer to EC-541
.
.OK or NG
OK >> • WITH CONSULT-III
GO TO 9.
• WITHOUT CONSULT-III
GO TO 10.
NG >> Replace as necessary.
9.CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to MTC-22, "
CONSULT-III Function (BCM)".
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10.CHECK BCM INPUT (FAN ON) SIGNAL
1. Turn ignition switch ON.
2. Turn blower control dial to "1" position.
3. Confirm fan on signal between front air control harness connec-
tor M33 terminal 14 and ground using oscilloscope.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL 1 - 27 :Continuity should exist
SJIA0759E
FAN CONTROL DIAL ON : FAN ON SIG ON
FAN CONTROL DIAL OFF : FAN ON SIG OFF
Te r m i n a l s
Voltag e
(Approx.) (+)
(-)
Connector Terminal
Front air con-
trol: M3314 Ground
SJIA0750E
ZJIA0583J

TROUBLE DIAGNOSIS
MTC-41
< SERVICE INFORMATION >
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MTC
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1. Turn ignition switch OFF.
2. Disconnect front air control connector and BCM connector.
3. Check continuity between BCM harness connector M18 (A) ter-
minal 28 and front air control harness connector M33 (B) termi-
nal 14.
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12.CHECK FAN SWITCH CIRCUIT
1. Turn blower control dial to the OFF position.
2. Check continuity between front air control terminals 9 and 14.
OK or NG
OK >> GO TO 13.
NG >> Replace front air control. Refer to MTC-55
.
13.CHECK FRONT AIR CONTROL GROUND CIRCUIT
Check continuity between front air control harness connector M33
terminal 9 and ground.
OK or NG
OK >> GO TO 14.
NG >> Repair harness or connector.
14.CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
1. Reconnect BCM connector and front air control connectors.
2. Turn ignition switch ON.
3. Turn blower control dial clockwise to position "1".
4. Confirm compressor on signal between front air control harness
connector M33 terminal 1 and ground using oscilloscope.
AB
Continuity
Connector Terminal Connector Terminal
BCM: M18 28Front air control:
M3314 Yes
SJIA0751E
9 - 14 :Continuity should exist
SJIA0753E
9 - Ground :Continuity should exist
SJIA0754E
SJIA0755E

MTC-42
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.
15.CHECK A/C SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect front air control connector.
3. While pressing the A/C switch, check continuity between front
air control terminals 1 and 8.
OK or NG
OK >> GO TO 16.
NG >> Replace front air control. Refer to MTC-55
.
16.CHECK FRONT AIR CONTROL GROUND CIRCUIT
Check continuity between front air control harness connector M33
terminal 8 and ground.
OK or NG
OK >> GO TO 17.
NG >> Repair harness or connector.
17.CHECK POWER SUPPLY FOR THERMO CONTROL AMP.
1. Turn ignition switch OFF.
2. Disconnect thermo control amp. connector.
3. Turn ignition switch ON.
4. Confirm thermo amp signal between thermo control amp. har-
ness connector M42 terminal 3 and ground using oscilloscope.
Te r m i n a l s
Vo l ta g e
(Approx.) (+)
(-)
Connector Terminal
Front air control:
M331Ground
ZJIA0584J
1 - 8 :Continuity should exist
SJIA0756E
8 - Ground :Continuity should exist
SJIA0758E
SJIA0760E

TROUBLE DIAGNOSIS
MTC-43
< SERVICE INFORMATION >
C
D
E
F
G
H
I
K
L
MA
B
MTC
N
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OK or NG
OK >> • GO TO 18 (with CVT).
• GO TO 19 (without CVT).
NG >> GO TO 21.
18.CHECK THERMO CONTROL AMP. GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between thermo control amp. harness connec-
tor M42 terminal 2 and ground.
OK or NG
OK >> Repair thermo control amp. jumper as necessary.
NG >> Repair harness or connector.
19.CHECK POWER SUPPLY FOR THERMO CONTROL AMP.
Check voltage between thermo control amp. harness connector M42
terminal 1 and ground.
OK or NG
OK >> GO TO 20.
NG >> Check power supply circuit and 10A fuse [No. 16,
located in the fuse block (JB)]. Refer to PG-72
.
• If fuse is OK, check harness for open circuit. Repair or
replace if necessary.
• If fuse is NG, replace fuse and check harness for short
circuit. Repair or replace if necessary.
20.CHECK THERMO CONTROL AMP. GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between thermo control amp. harness connec-
tor M42 terminal 2 and ground.
OK or NG
OK >> Replace thermo control amp. Refer to MTC-57.
NG >> Repair harness or connector.
21.CHECK CIRCUIT CONTINUITY BETWEEN THERMO CONTROL AMP. AND BCM
Te r m i n a l s
Vol tag e
(Approx.) (+)
(-)
Connector Terminal
Thermo control
amp.: M423Ground
ZJIA0719J
2 - Ground :Continuity should exist
SJIA0763E
1 - Ground :Battery voltage
SJIA0762E
2 - Ground :Continuity should exist
SJIA0763E

MTC-44
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Disconnect BCM connector.
3. Check continuity between thermo control amp. harness connec-
tor M42 (A) terminal 3 and BCM harness connector M18 (B) ter-
minal 26.
OK or NG
OK >> GO TO 22.
NG >> Repair harness or connector.
22.CHECK CAN COMMUNICATION
Check CAN communication. Refer to LAN-15, "Trouble Diagnosis Flow Chart".
•BCM – ECM
• ECM – IPDM E/R
OK or NG
OK >> Replace BCM. Refer to BCS-18, "Removal and Installation of BCM".
NG >> Repair or replace malfunctioning part(s).
23.CHECK DEFROST A/C SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect BCM connector.
3. Press the defrost A/C switch.
NOTE:
The defrost A/C switch is located on back side of the front air
control.
4. Check continuity between BCM harness connector M18 terminal
10 and ground.
OK or NG
OK >> Replace BCM. Refer to BCS-18, "Removal and Installation of BCM".
NG >> GO TO 24.
24.CHECK CIRCUIT CONTINUITY BETWEEN DEFROST A/C SWITCH AND BCM
1. Disconnect defrost A/C switch connector.
2. Check continuity between BCM harness connector M18 (B) ter-
minal 10 and defrost A/C switch harness connector M41 (A) ter-
minal 15.
OK or NG
OK >> GO TO 25.
NG >> Repair harness or connector.
25.CHECK CIRCUIT CONTINUITY BETWEEN DEFROST A/C SWITCH AND GROUND 3 - 26 :Continuity should exist
SJIA0764E
10 - Ground :Continuity should exist
WJIA2252E
10 - 15 :Continuity should exist
WJIA2254E