2008 NISSAN LATIO relay

MTC-14
< SERVICE INFORMATION >
REFRIGERATION SYSTEM
REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000001704286
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator is
controlled by an externally equalized expansion valve, located inside the evaporator case.
FREEZE PROTECTION
Under usual operating conditions, when the A/C is switched ON, the compressor runs continuously, and the
evaporator pressure, and temperature is controlled by the compressor to prevent freeze up.
Refrigerant System ProtectionINFOID:0000000001704287
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above, or falls below the specifications, the refrig-
erant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.
ECM makes the A/C relay go OFF and stops the compressor when pressure on the high-pressure side
detected by refrigerant pressure sensor is over about 2,746 kPa (27.46 bar, 28.0 kg/cm
2 , 398 psi), or below
about 134 kPa (1.34 bar, 1.4 kg/cm
2 , 20 psi).
PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system increases to an unusual level [more than 3.8 MPa (38 bar,
38.76 kg/cm
2 , 551 psi)], the release port on the pressure relief valve automatically opens and releases refrig-
erant into the atmosphere.
RJIA0849E

TROUBLE DIAGNOSIS
MTC-35
< SERVICE INFORMATION >
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NG >> Check power supply circuit and 15A fuses [Nos. 15 and 17, located in the fuse block (J/B)].
Refer to PG-3, "
Schematic".
• If fuses are OK, reinstall fuses and GO TO 3.
• If fuses are NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
3.CHECK BLOWER MOTOR RELAY POWER SUPPLY CIRCUITS
1. Turn ignition switch OFF.
2. Disconnect blower motor relay connector.
3. Turn ignition switch ON.
4. Check voltage between blower motor relay harness connector J-
1 terminal 1, 5 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4.CHECK BLOWER MOTOR RELAY (SWITCH SIDE) CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Check continuity between blower motor relay harness connector
J-1 (A) terminal 3 and front blower motor harness connector
M62 (B) terminal 1.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5.CHECK BLOWER MOTOR RELAY GROUND CIRCUIT
Check continuity between blower motor relay harness connector J-1
terminal 2 and ground.
OK or NG
OK >> Replace blower motor relay.
NG >> Repair harness or connector.
6.CHECK FRONT BLOWER MOTOR
Check continuity between front blower motor terminals 1 and 2.
NOTE:
Ensure that there are no foreign particles inside the A/C unit assem-
bly for a smooth rotation of the front blower motor.
OK or NG
OK >> GO TO 7.
NG >> Replace front blower motor. Refer to MTC-62, "
Removal
and Installation".
7.CHECK CIRCUIT CONTINUITY BETWEEN FRONT BLOWER MOTOR AND FRONT AIR CONTROL 1 - Ground Battery voltage should exist.
5 - Ground Battery voltage should exist.
WJIA1783E
Continuity should exist.
WJIA2263E
Continuity should exist.
WJIA2264E
1 - 2 : Continuity should exist.
WJIA2230E

PG-1
ELECTRICAL
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CONTENTS
POWER SUPPLY, GROUND & CIRCUIT ELEMENTS
SERVICE INFORMATION ............................2
PRECAUTIONS ...................................................2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
2
POWER SUPPLY ROUTING CIRCUIT ...............3
Schematic .................................................................3
Wiring Diagram - POWER - ......................................5
Fuse ........................................................................15
Fusible Link .............................................................15
Circuit Breaker (Built Into BCM) ..............................15
Circuit Breaker ........................................................15
IPDM E/R (INTELLIGENT POWER DISTRI-
BUTION MODULE ENGINE ROOM) .................
16
System Description .................................................16
CAN Communication System Description ...............17
Function of Detecting Ignition Relay Malfunction ....17
CONSULT-III Function (IPDM E/R) .........................17
Auto Active Test ......................................................19
IPDM E/R Terminal Arrangement ...........................22
Terminal and Reference Value for IPDM E/R .........23
IPDM E/R Power/Ground Circuit Inspection ...........25
Inspection with CONSULT-III (Self-Diagnosis) .......26
Removal and Installation of IPDM E/R ....................26
GROUND CIRCUIT ...........................................28
Ground Distribution ..................................................28
HARNESS .........................................................37
Harness Layout .......................................................37
Wiring Diagram Codes (Cell Codes) .......................58
ELECTRICAL UNITS LOCATION ....................61
Electrical Units Location ..........................................61
HARNESS CONNECTOR .................................65
Description ...............................................................65
ELECTRICAL UNITS ........................................68
Terminal Arrangement .............................................68
STANDARDIZED RELAY .................................69
Description ...............................................................69
SUPER MULTIPLE JUNCTION (SMJ) .............71
Terminal Arrangement .............................................71
FUSE BLOCK-JUNCTION BOX (J/B) ..............72
Terminal Arrangement .............................................72
FUSE AND FUSIBLE LINK BOX ......................73
Terminal Arrangement .............................................73

PG-16
< SERVICE INFORMATION >
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE
ROOM)
System DescriptionINFOID:0000000001704697
• IPDM E/R (Intelligent Power Distribution Module Engine Room) integrates the relay box and fuse block
which were originally placed in engine compartment. It controls integrated relays via IPDM E/R control cir-
cuits.
• IPDM E/R-integrated control circuits perform ON-OFF operation of relays, CAN communication control, oil
pressure switch signal reception, etc.
• It controls operation of each electrical component via ECM, BCM and CAN communication lines.
CAUTION:
None of the IPDM E/R integrated relays can be removed.
SYSTEMS CONTROLLED BY IPDM E/R
1. Lamp control
Using CAN communication lines, it receives signals from the BCM and controls the following lamps:
• Headlamps (High, Low)
• Parking lamps
• Tail and license plate lamps
• Front fog lamps
2. Wiper control
Using CAN communication lines, it receives signals from the BCM and controls the front wipers.
3. Rear window defogger relay control
Using CAN communication lines, it receives signals from the BCM and controls the rear window defogger
relay.
4. A/C compressor control
Using CAN communication lines, it receives signals from the ECM and controls the A/C compressor
(magnet clutch).
5. Starter control
Using CAN communication lines, it receives signals from the BCM and controls the starter relay.
6. Cooling fan control
Using CAN communication lines, it receives signals from the ECM and controls the cooling fan relays.
7. Horn control
Using CAN communication lines, it receives signals from the BCM and controls the horn relay.
8. Daytime light system control (Canada only)
Using CAN communication lines, it receives signals from the BCM and controls the daytime light relay.
CAN COMMUNICATION LINE CONTROL
With CAN communication, by connecting each control unit using two communication lines (CAN L-line, CAN
H-line), it is possible to transmit a maximum amount of information with minimum wiring. Each control unit can
transmit and receive data, and reads necessary information only.
1. Fail-safe control
• When CAN communication with other control units is impossible, IPDM E/R performs fail-safe control.
After CAN communication returns to normal operation, it also returns to normal control.
• Operation of control parts by IPDM E/R during fail-safe mode is as follows:
Controlled system Fail-safe mode
Headlamp• With the ignition switch ON, headlamp low relay is ON, headlamp high relays are OFF, and
daytime light system (Canada only) is OFF.
• With the ignition switch OFF, the headlamp relays are OFF.
Tail, license plate and parking lamps • With the ignition switch ON, the tail lamp relay is ON.
• With the ignition switch OFF, the tail lamp relay is OFF.
Cooling fan• With the ignition switch ON, cooling fan relay-1, relay-2, and relay-3 are ON.
• With the ignition switch OFF, all cooling fan relays are OFF.
Front wiperUntil the ignition switch is turned off, the front wiper relays remain in the same status they
were in just before fail−safe control was initiated.

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PG-17
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IPDM E/R STATUS CONTROL
In order to save power, IPDM E/R switches status by itself based on each operating condition.
1. CAN communication status
• CAN communication is normally performed with other control units.
• Individual unit control by IPDM E/R is normally performed.
• When sleep request signal is received from BCM, mode is switched to sleep waiting status.
2. Sleep waiting status
• Process to stop CAN communication is activated.
• All systems controlled by IPDM E/R are stopped. When 1 second has elapsed after CAN communica-
tion with other control units is stopped, mode switches to sleep status.
3. Sleep status
• IPDM E/R operates in low current-consumption mode.
• CAN communication is stopped.
• When a change in CAN communication signal is detected, mode switches to CAN communication sta-
tus.
• When a change in ignition switch signal is detected, mode switches to CAN communication status.
CAN Communication System DescriptionINFOID:0000000001704698
Refer to LAN-6, "System Description".
Function of Detecting Ignition Relay MalfunctionINFOID:0000000001704699
• When the integrated ignition relay is stuck in a "closed contact" position and cannot be turned OFF, IPDM E/
R turns ON tail and parking lamps for 10 minutes to indicate IPDM E/R malfunction.
• When the state of the integrated ignition relay does not agree with the state of the ignition switch signal
received via CAN communication, the IPDM E/R activates the tail lamp relay.
NOTE:
When the ignition switch is turned ON, the tail lamps are OFF.
CONSULT-III Function (IPDM E/R)INFOID:0000000001704700
CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.
SELF-DIAGNOSTIC RESULTS
Display Item List
Rear window defogger Rear window defogger relay OFF
A/C compressor A/C relay is OFF
Front fog lamps Front fog lamp relay OFFControlled system Fail-safe mode
Ignition switch signal Ignition relay status Tail lamp relay
ON ON —
OFF OFF —
ON OFF —
OFF ON ON (10 minutes)
IPDM E/R diagnostic Mode Description
SELF-DIAG RESULTS Displays IPDM E/R self-diagnosis results.
DATA MONITOR Displays IPDM E/R input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.

PG-18
< SERVICE INFORMATION >
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
x: Applicable
NOTE:
The details for display of the period are as follows:
• CRNT: Error currently detected with IPDM E/R.
• PAST: Error detected in the past and placed in IPDM E/R memory.
DATA MONITOR
All Signals, Main Signals, Selection From Menu
Display itemsCONSULT-
III display
codeMalfunction detectionTIME
Possible causes
CRNT PAST
NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED.—————
CAN COMM CIRC U1000• If CAN communication reception/transmission
data has a malfunction, or if any of the control
units fail, data reception/transmission cannot be
confirmed.
• When the data in CAN communication is not re-
ceived before the specified time.XXAny of items listed
below have errors:
• TRANSMIT DIAG
•ECM
• BCM/SEC
IGN RELAY ON —When the ignition switch is not in the ON position,
the ignition relay in the IPDM E/R is ON.XX
IGN RELAY OFF —When the ignition switch is not in the ON position,
the ignition relay in the IPDM E/R is OFF.XX
EEPROM —Malfunction is detected with the integrated EEPROM
memory diagnosis.XX
Item nameCONSULT-III
screen display Display or unitMonitor item selection
Description
ALL
SIGNALSMAIN
SIGNALSSELECTION
FROM MENU
Motor fan requestMOTOR FAN
REQ1/2/3/4 X X X Signal status input from ECM
Compressor re-
questAC COMP REQ ON/OFF X X X Signal status input from ECM
Parking, license,
and tail lamp re-
questTAIL & CLR REQ ON/OFF X X X Signal status input from BCM
Headlamp low
beam requestHL LO REQ ON/OFF X X X Signal status input from BCM
Headlamp high
beam requestHL HI REQ ON/OFF X X X Signal status input from BCM
Front fog request FR FOG REQ ON/OFF X X X Signal status input from BCM
FR wiper request FR WIP REQ STOP/1LO/LO/HI X X X Signal status input from BCM
Wiper auto stopWIP AUTO
STOPACT P/STOP P X X X Output status of IPDM E/R
Wiper protection WIP PROT OFF/LS/HS/Block X X X Control status of IPDM E/R
Starter request ST RLY REQ ON/OFF X X Status of input signal (*1)
Ignition relay
statusIGN RLY ON/OFF X X XIgnition relay status monitored
with IPDM E/R
Rear defogger re-
questRR DEF REQ ON/OFF X X X Signal status input from BCM
Oil pressure
switchOIL P SW OPEN/CLOSE X XSignal status input from IPDM
E/R
Hood switch HOOD SW (*2) OFF X XSignal status input from IPDM
E/R

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PG-19
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*1 Perform monitoring of IPDM E/R data with the ignition switch ON. When the ignition switch is in ACC position, display may not be cor-
rect.
*2 This item is displayed, but does not function.
CAN DIAG SUPPORT MNTR
Refer to LAN-8 .
ACTIVE TEST
Display Item List
Auto Active TestINFOID:0000000001704701
DESCRIPTION
• In auto active test mode, operation inspection can be performed when IPDM E/R sends a drive signal to the
following systems:
- Rear window defogger
- Front wipers
- Tail, license and parking lamps
- Daytime lamp system (Canada only)
- Front fog lamps
- Headlamps (High, Low)
- A/C compressor (magnet clutch)
- Cooling fan
OPERATION PROCEDURE
1. Close hood and front door RH, and lift wiper arms away from windshield (to prevent glass damage by
wiper operation).
NOTE:
When auto active test is performed with hood opened, sprinkle water on windshield beforehand.
2. Turn ignition switch OFF.
3. Turn ignition switch ON and, within 20 seconds, press front door switch LH 20 times. Then turn ignition
switch OFF.
4. Turn ignition switch ON within 10 seconds after ignition switch OFF.
5. When auto active test mode is actuated, horn chirps once.
6. After a series of operations is repeated three times, auto active test is completed.
Theft warning
horn requestTHFT HRN REQ ON/OFF X X Signal status input from BCM
Horn chirp HORN CHIRP ON/OFF X X Output status of IPDM E/R
Daytime light re-
questDTRL REQ ON/OFF X X Signal status input from BCM Item nameCONSULT-III
screen display Display or unitMonitor item selection
Description
ALL
SIGNALSMAIN
SIGNALSSELECTION
FROM MENU
Test name CONSULT-III screen display Description
Head, tail, fog lamp output EXTERNAL LAMPSWith a certain ON-OFF operation (OFF, TAIL, LO, HI, FOG), the front
fog lamp, headlamp low, headlamp high RH, headlamp high LH, and
tail lamp relays can be operated.
Rear defogger output REAR DEFOGGERWith a certain ON-OFF operation, the rear defogger relay can be oper-
ated.
Front wiper (HI, LO) output FRONT WIPERWith a certain operation (OFF, HI ON, LO ON), the front wiper relays
(Lo, Hi) can be operated.
Cooling fan output MOTOR FANWith a certain operation (1, 2, 3, 4), the cooling fan relays can be oper-
ated.
Horn output HORN With a certain ON-OFF operation, the horn relay can be operated.

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PG-21
< SERVICE INFORMATION >
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• IPDM E/R actuates auto active test mode when it receives door switch signal from BCM via CAN communi-
cation line. Therefore, when auto active test mode is activated successfully, CAN communication between
IPDM E/R and BCM is normal.
• If any of the systems controlled by IPDM E/R cannot be operated, possible cause can be easily diagnosed
using auto active test.
Diagnosis chart in auto active test mode
WKIA5665E
Symptom Inspection contents Possible cause
Rear window defogger
does not operate.Perform auto active
test. Does rear win-
dow defogger oper-
ate?YES • BCM signal input circuit
NO• Rear window defogger relay
• Open circuit of rear window defogger
• IPDM E/R malfunction
• Harness or connector malfunction between IPDM E/R and rear window
defogger
Any of front wipers, tail
and parking lamps, front
fog lamps, daytime light
system (Canada only),
and headlamps (High,
Low) do not operate.Perform auto active
test. Does system in
question operate?YES • BCM signal input system
NO• Lamp/wiper motor malfunction
• Lamp/wiper motor ground circuit malfunction
• Harness/connector malfunction between IPDM E/R and system in ques-
tion
• IPDM E/R (integrated relay) malfunction
A/C compressor does
not operate.Perform auto active
test. Does magnet
clutch operate?YES• BCM signal input circuit
• CAN communication signal between BCM and ECM
• CAN communication signal between ECM and IPDM E/R
NO• Magnet clutch malfunction
• Harness/connector malfunction between IPDM E/R and magnet clutch
• IPDM E/R (integrated relay) malfunction
Cooling fan does not op-
erate.Perform auto active
test. Does cooling fan
operate?YES• ECM signal input circuit
• CAN communication signal between ECM and IPDM E/R
NO• Cooling fan motor malfunction
• Harness/connector malfunction between IPDM E/R and cooling fan mo-
tor
• IPDM E/R (integrated relay) malfunction
Oil pressure warning
lamp does not operate.Perform auto active
test. Does oil pressure
warning lamp blink?YES• Harness/connector malfunction between IPDM E/R and oil pressure
switch
• Oil pressure switch malfunction
• IPDM E/R
NO• CAN communication signal between BCM and combination meter
• Combination meter