Observe the following precautions to ensure safe and proper
servicing. These precautions are not described in each indi-
vidual section.
Precaution for Supplemental Restraint System
(SRS) ``AIR BAG'' and ``SEAT BELT
PRE-TENSIONER''
The Supplemental Restraint System such as ``AIR BAG'' and
``SEAT BELT PRE-TENSIONER'' used along with a seat belt, helps
to reduce the risk or severity of injury to the driver and front pas-
senger in a frontal collision. The SRS system composition which is
available to NISSAN MODEL Y61 is as follows (The composition
varies according to the destination.):
Driver air bag module (located in the center of the steering wheel),
front passenger air bag module (located on the instrument panel on
passenger side), seat belt pre-tensioner, a diagnosis sensor unit,
warning lamp, wiring harness and spiral cable.
Information necessary to service the system safely is included in
theRS sectionof this Service Manual.
WARNING:
+To avoid rendering the SRS inoperative, which could
increase the risk of personal injury or death in the event of
a collision which would result in air bag in¯ation, all main-
tenance must be performed by an authorized NISSAN
dealer.
+Improper maintenance, including incorrect removal and
installation of the SRS, can lead to personal injury caused
by unintentional activation of the system. For removal of
Spiral Cable and Air Bag Module, see the RS section.
+Do not use electrical test equipment on any circuit related
to the SRS unless instructed to in this Service Manual.
Spiral cable and wiring harnesses are covered with yellow
insulation either just before the harness connectors or for
the complete harness are related to the SRS.
SGI646
PRECAUTIONS
GI-1
Description
Number Item Description
V1Power condition+This shows the condition when the system receives battery positive voltage (can
be operated).
V2Fusible link+The double line shows that this is a fusible link.
+The open circle shows current ¯ow in, and the shaded circle shows current ¯ow
out.
V3Fusible link/fuse location+This shows the location of the fusible link or fuse in the fusible link or fuse box.
For arrangement, refer to EL section (``POWER SUPPLY ROUTING'').
V4Fuse+The single line shows that this is a fuse.
+The open circle shows current ¯ow in, and the shaded circle shows current ¯ow
out.
V5Current rating+This shows the current rating of the fusible link or fuse.
V6Connectors+This shows that connector
E3is female and connectorM1is male.
+The G/R wire is located in the 1A terminal of both connectors.
+Terminal number with an alphabet (1A, 5B, etc.) indicates that the connector is
SMJ connector. Refer to GI-16.
V7Optional splice+The open circle shows that the splice is optional depending on vehicle application.
V8Splice+The shaded circle shows that the splice is always on the vehicle.
V9Page crossing+This arrow shows that the circuit continues to an adjacent page.
+The A will match with the A on the preceding or next page.
V10Common connector+The dotted lines between terminals show that these terminals are part of the same
connector.
V11Option abbreviation+This shows that the circuit is optional depending on vehicle application.
V12Relay+This shows an internal representation of the relay. For details, refer to EL section
(``STANDARDIZED RELAY'').
V13Connectors+This shows that the connector is connected to the body or a terminal with bolt or
nut.
V14Wire color+This shows a code for the color of the wire.
B = Black BR = Brown
W = White OR = Orange
R = Red P = Pink
G = Green PU = Purple
L = Blue GY = Gray
Y = Yellow SB = Sky Blue
LG = Light Green CH = Dark Brown
DG = Dark Green
When the wire color is striped, the base color is given ®rst, followed by the stripe
color as shown below:
Example: L/W = Blue with White Stripe
V15Option description+This shows a description of the option abbreviation used on the page.
V16Switch+This shows that continuity exists between terminals 1 and 2 when the switch is in
the A position. Continuity exists between terminals 1 and 3 when the switch is in
the B position.
V17Assembly parts+Connector terminal in component shows that it is a harness incorporated assem-
bly.
V18Cell code+This identi®es each page of the wiring diagram by section, system and wiring dia-
gram page number.
HOW TO READ WIRING DIAGRAMS
GI-10
Number Item Description
V19Current ¯ow arrow+Arrow indicates electric current ¯ow, especially where the direction of standard
¯ow (vertically downward or horizontally from left to right) is difficult to follow.
+A double arrow ``bÐ
c'' shows that current can ¯ow in either direction depending
on circuit operation.
V20System branch+This shows that the system branches to another system identi®ed by cell code
(section and system).
V21Page crossing+This arrow shows that the circuit continues to another page identi®ed by cell code.
+The C will match with the C on another page within the system other than the
next or preceding pages.
V22Shielded line+The line enclosed by broken line circle shows shield wire.
V23Component box in wave
line+This shows that another part of the component is also shown on another page
(indicated by wave line) within the system.
V24Component name+This shows the name of a component.
V25Connector number+This shows the connector number.
+The letter shows which harness the connector is located in.
Example:M: main harness. For detail and to locate the connector, refer to EL sec-
tion (``Main Harness'', ``HARNESS LAYOUT''). A coordinate grid is included for
complex harnesses to aid in locating connectors.
V26Ground (GND)+The line spliced and grounded under wire color shows that ground line is spliced
at the grounded connector.
V27Ground (GND)+This shows the ground connection.
V28Connector views+This area shows the connector faces of the components in the wiring diagram on
the page.
V29Common component+Connectors enclosed in broken line show that these connectors belong to the
same component.
V30Connector color+This shows a code for the color of the connector. For code meaning, refer to wire
color codes, NumberV14of this chart.
V31Fusible link and fuse box+This shows the arrangement of fusible link(s) and fuse(s), used for connector
views of ``POWER SUPPLY ROUTING'' in EL section.
The open square shows current ¯ow in, and the shaded square shows current
¯ow out.
V32Reference area+This shows that more information on the Super Multiple Junction (SMJ) and Joint
Connectors (J/C) exists on the foldout page. Refer to GI-16 for details.
HOW TO READ WIRING DIAGRAMS
Description (Cont'd)
GI-11
CONNECTOR SYMBOLS
Most of connector symbols in wiring diagrams are shown from the
terminal side.
+Connector symbols shown from the terminal side are enclosed
by a single line and followed by the direction mark
.
+Connector symbols shown from the harness side are enclosed
by a double line and followed by the direction mark
.
+Male and female terminals
Connector guides for male terminals are shown in black and
female terminals in white in wiring diagrams.
SGI364
SGI363
HOW TO READ WIRING DIAGRAMS
Description (Cont'd)
GI-12
Harness indication
+Letter designations next to test meter probe indicate harness
(connector) wire color.
+Connector numbers in a single circle
M33indicate harness con-
nectors.
Component indication
+Connector numbers in a double circle indicate component con-
nectors.
SWITCH POSITIONS
Switches are shown in wiring diagrams as if the vehicle is in the
``normal'' condition.
A vehicle is in the ``normal'' condition when:
+ignition switch is ``OFF'',
+doors, hood and trunk lid/back door are closed,
+pedals are not depressed, and
+parking brake is released.
AGI070
SGI860
HOW TO READ WIRING DIAGRAMS
Description (Cont'd)
GI-13
Work Flow
STEP DESCRIPTION
STEP 1 Get detailed information about the conditions and the environment when the incident occurred.
The following are key pieces of information required to make a good analysis:
WHATVehicle Model, Engine, Transmission and the System (i.e. Radio).
WHENDate, Time of Day, Weather Conditions, Frequency.
WHERERoad Conditions, Altitude and Traffic Situation.
HOWSystem Symptoms, Operating Conditions (Other Components Interaction).
Service History and if any After Market Accessories have been installed.
STEP 2 Operate the system, road test if necessary.
Verify the parameter of the incident.
If the problem can not be duplicated, refer to ``Incident Simulation Tests'' next page.
STEP 3 Get the proper diagnosis materials together including:
POWER SUPPLY ROUTING
System Operation Descriptions
Applicable Service Manual Sections
Check for any Service Bulletin.
Identify where to begin diagnosis based upon your knowledge of the system operation and the customer comments.
STEP 4 Inspect the system for mechanical binding, loose connectors or wiring damage.
Determine which circuits and components are involved and diagnose using the Power Supply Routing and Harness
Layouts.
STEP 5 Repair or replace the incident circuit or component.
STEP 6 Operate the system in all modes. Verify the system works properly under all conditions. Make sure you have not inad-
vertently created a new incident during your diagnosis or repair steps.
SGI838
HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
GI-20
Incident Simulation Tests
INTRODUCTION
Sometimes the symptom is not present when the vehicle is brought in for service. If possible, re-create the
conditions present at the time of the incident. Doing so may help avoid a No Trouble Found Diagnosis. The
following section illustrates ways to simulate the conditions/environment under which the owner experiences
an electrical incident.
The section is broken into the six following topics:
+Vehicle vibration
+Heat sensitive
+Freezing
+Water intrusion
+Electrical load
+Cold or hot start up
Get a thorough description of the incident from the customer. It is important for simulating the conditions of
the problem.
VEHICLE VIBRATION
The problem may occur or become worse while driving on a rough road or when engine is vibrating (idle with
A/C on). In such a case, you will want to check for a vibration related condition. Refer to the illustration below.
Connectors & harness
Determine which connectors and wiring harness would affect the electrical system you are inspecting.Gen-
tlyshake each connector and harness while monitoring the system for the incident you are trying to dupli-
cate. This test may indicate a loose or poor electrical connection.
Hint
Connectors can be exposed to moisture. It is possible to get a thin ®lm of corrosion on the connector termi-
nals. A visual inspection may not reveal this without disconnecting the connector. If the problem occurs
intermittently, perhaps the problem is caused by corrosion. It is a good idea to disconnect, inspect and clean
the terminals on related connectors in the system.
Sensors & relays
Gentlyapply a slight vibration to sensors and relays in the system you are inspecting.
This test may indicate a loose or poorly mounted sensor or relay.
SGI839
HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
GI-21
Engine compartment
There are several reasons a vehicle or engine vibration could
cause an electrical complaint. Some of the things to check for are:
+Connectors not fully seated.
+Wiring harness not long enough and is being stressed due to
engine vibrations or rocking.
+Wires laying across brackets or moving components.
+Loose, dirty or corroded ground wires.
+Wires routed too close to hot components.
To inspect components under the hood, start by verifying the integ-
rity of ground connections. (Refer to GROUND INSPECTION
described later.) First check that the system is properly grounded.
Then check for loose connection bygently shakingthe wiring or
components as previously explained. Using the wiring diagrams
inspect the wiring for continuity.
Behind the instrument panel
An improperly routed or improperly clamped harness can become
pinched during accessory installation. Vehicle vibration can aggra-
vate a harness which is routed along a bracket or near a screw.
Under seating areas
An unclamped or loose harness can cause wiring to be pinched by
seat components (such as slide guides) during vehicle vibration. If
the wiring runs under seating areas, inspect wire routing for pos-
sible damage or pinching.
HEAT SENSITIVE
The owner's problem may occur during hot weather or after car has
sat for a short time. In such cases you will want to check for a heat
sensitive condition.
To determine if an electrical component is heat sensitive, heat the
component with a heat gun or equivalent.
Do not heat components above 60ÉC (140ÉF).If incident occurs
while heating the unit, either replace or properly insulate the com-
ponent.
SGI842
HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont'd)
GI-22