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CCS-178
< SYSTEM DESCRIPTION >[ASCD]
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
SYSTEM DESCRIPTION
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
InformationINFOID:0000000006289721
Automatic Speed Control Device (ASCD) system is controlled by ECM.
Regarding the information for ASCD system, refer to following;
VK56VD:
EC-48, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD) : System Description"
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ELECTRICAL & POWER CONTROL
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CONTENTS
CHARGING SYSTEM
PRECAUTION ................
...............................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
3
Precaution for Power Generation Voltage Variable
Control System ..........................................................
4
PREPARATION ............................................5
PREPARATION .............................................. .....5
Special Service Tools .......................................... ......5
Commercial Service Tools ........................................5
SYSTEM DESCRIPTION ..............................6
COMPONENT PARTS ................................... .....6
Component Parts Location .................................. ......6
Component Description ............................................6
SYSTEM ..............................................................7
CHARGING SYSTEM ..................................................7
CHARGING SYSTEM : System Diagram ........... ......7
CHARGING SYSTEM : System Description .............7
POWER GENERATION VOLTAGE VARIABLE
CONTROL SYSTEM .............................................. ......
7
POWER GENERATION VOLTAGE VARIABLE
CONTROL SYSTEM : System Diagram ...................
7
POWER GENERATION VOLTAGE VARIABLE
CONTROL SYSTEM : System Description ...............
7
WIRING DIAGRAM ........ ...............................9
CHARGING SYSTEM ..................................... .....9
Wiring Diagram ................................................... ......9
BASIC INSPECTION ...................................13
DIAGNOSIS AND REPAIR WORKFLOW ........13
Work Flow ............................................................ ....13
CHARGING SYSTEM PRELIMINARY IN-
SPECTION ....................................... .................
16
Inspection Procedure ........................................... ....16
POWER GENERATION VOLTAGE VARI-
ABLE CONTROL SYSTEM OPERATION IN-
SPECTION ....................................... .................
17
Inspection Procedure ........................................... ....17
DTC/CIRCUIT DIAGNOSIS .........................19
B TERMINAL CIRCUIT .....................................19
Description ........................................................... ....19
Diagnosis Procedure ...............................................19
L TERMINAL CIRCUIT (OPEN) ........................20
Description ...............................................................20
Diagnosis Procedure ...............................................20
L TERMINAL CIRCUIT (SHORT) .....................22
Description ...............................................................22
Diagnosis Procedure ...............................................22
S TERMINAL CIRCUIT .....................................23
Description ...............................................................23
Diagnosis Procedure ...............................................23
SYMPTOM DIAGNOSIS ..............................24
CHARGING SYSTEM .......................................24
Symptom Table ................................................... ....24
REMOVAL AND INSTALLATION ...............25
ALTERNATOR ................................. .................25
Exploded View ..................................................... ....25
Removal and Installation .........................................26
Inspection ................................................................28
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CHG-2
SERVICE DATA AND SPECIFICATIONS
(SDS) .............. .............................................
29
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ...
29
Alternator ............................................................. ...29
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< PRECAUTION >
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006274854
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric power tools or strike near the sensor(s)
with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly
causing serious injury.
When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006274855
NOTE:
Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect both battery cables.
After finishing work, confirm that all control unit connectors are connected properly, then re-connect both
battery cables.
Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If a DTC is detected, perform trouble diagnos is according to self-diagnosis results.
For vehicle with steering lock unit, if the battery is disconnected or discharged, the steering wheel will lock and
cannot be turned.
If turning the steering wheel is required with the batte ry disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wil l remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
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< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, re-connect both battery cables. With the brake pedal released, turn
the push-button ignition switch from ACC position to ON position, then to LOCK position. (The steering
wheel will lock when the push-button igniti on switch is turned to LOCK position.)
6. Perform self-diagnosis check of all control units using CONSULT-III.
Precaution for Power Generation Vo ltage Variable Control SystemINFOID:0000000006274856
CAUTION:
For this model, the battery current sensor that is in stalled to the battery cable at the negative terminal
measures the charging/discharging curre nt of the battery, and performs various controls. If the electri-
cal component or the ground wire is connected direct ly to the battery terminal, the current other than
that being measured with the battery current sensor is charging to or discharging from the battery.
This condition causes the malfunction of the control, and then the battery discharge may occur. Do
not connect the electrical compon ent or the ground wire directly to the battery terminal.
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< PREPARATION >
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PREPARATION
PREPARATION
Special Service ToolsINFOID:0000000006274882
Commercial Service ToolsINFOID:0000000006274883
Tool number
(Kent-Moore No.) Tool name Description
—
(J-44373 Model MCR620)
Starting/Charging System Tester Tests starting and charging systems.
For operating instructio
ns, refer to Technical
Service Bulletin.
SEL403X
Tool name Description
Power tool Loosening bolts, nuts and screws
PIIB1407E
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< SYSTEM DESCRIPTION >
COMPONENT PARTS
SYSTEM DESCRIPTION
COMPONENT PARTS
Component Parts LocationINFOID:0000000006274858
Component DescriptionINFOID:0000000006274859
1. IPDM E/RRefer to PCS-4, "
Component Parts
Location". 2. ECM
Refer to EC-16, "
Component Parts
Location". 3. Battery current sensor
Refer to EC-16, "
Component Parts
Location".
4. Alternator 5. Combination meter (charge warning lamp)
Refer to MWI-6, "
METER SYSTEM :
Component Parts Location".
A. Engine room (RH)
JMMIA0411ZZ
Component part Description
Alternator (IC voltage regulator) IC voltage regulator controls the power generation voltage by the target power genera-
tion voltage based on the received power generation command signal.
When there is no power generation command signal, the alternator performs the normal
power generation according to the characteristic of the IC voltage regulator.
Battery current sensor Battery current sensor is installed to the battery cable at the negative terminal, and it de-
tects the charging/discharging current of the battery and sends the voltage signal to ECM
according to the current value.
Combination meter (C harge warning lamp) The IC voltage regulator warning function activates to illuminate the charge warning
lamp, if any of the following symptoms occur while alternator is operating:
Excessive voltage is produced.
No voltage is produced.
ECM Battery current sensor detects the charging/discharging current of the battery. ECM judg-
es the battery condition based on this signal.
ECM judges whether to perform the power generation voltage variable control according
to the battery condition.
When performing the power generation voltage variable control, ECM calculates the tar-
get power generation voltage according to the battery condition and sends the calculated
value as the power generation command value to IPDM E/R.
IPDM E/R IPDM E/R converts the received power generation command value into the power gen-
eration command signal (PWM signal) and sends it to the IC voltage regulator.
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< SYSTEM DESCRIPTION >
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SYSTEM
CHARGING SYSTEM
CHARGING SYSTEM : System DiagramINFOID:0000000006274860
CHARGING SYSTEM : System DescriptionINFOID:0000000006274861
The alternator provides DC voltage to operate the vehi
cle's electrical system and to keep the battery charged.
The voltage output is controlled by the IC voltage regulator.
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
POWER GENERATION VOLTAGE VARIABL E CONTROL SYSTEM : System Dia-
gram
INFOID:0000000006274862
POWER GENERATION VOLTAGE VARIABL E CONTROL SYSTEM : System De-
JPMIA0633GB
JPMIA0632GB
Revision: 2010 May2011 QX56