2003 NISSAN ALMERA N16 Ac system

Description=NJGI0003S02
Number Item Description
1 Power conditionThis shows the condition when the system receives battery positive voltage (can be
operated).
2 Fusible linkThe double line shows that this is a fusible link.
The open circle shows current flow in, and the shaded circle shows current flow out.
3Fusible link/fuse loca-
tionThis shows the location of the fusible link or fuse in the fusible link or fusebox.For
arrangement, refer to EL-12, “POWER SUPPLY ROUTING”.
4FuseThe single line shows that this is a fuse.
The open circle shows current flow in, and the shaded circle shows current flow out.
5 Current rating This shows the current rating of the fusible link or fuse.
6 ConnectorsThis shows that connector E3 is female and connector M1 is 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 con-
nector. Refer to GI-20.
7 Optional splice The open circle shows that the splice is optional depending on vehicle application.
8 Splice The shaded circle shows that the splice is always on the vehicle.
9 Page crossingThis arrow shows that the circuit continues to an adjacent page.
The A will match with the A on the preceding or next page.
10 Common connectorThe dotted lines between terminals show that these terminals are part of thesamecon-
nector.
11 Option abbreviation This shows that the circuit is optional depending on vehicle application.
12 RelayThis shows an internal representation of the relay. For details, refer to EL-9, “STAN-
DARDIZED RELAY”.
13 Connectors This shows that the connector is connected to the body or a terminal with bolt or nut.
14 Wire colorThis shows a code for the color of the wire.
B=Black
W = White
R = Red
G = Green
L = Blue
Y = Yellow
LG = Light GreenBR = Brown
OR = Orange
P = Pink
PU = Purple
GY = Gray
SB = Sky Blue
CH = Dark Brown
DG=DarkGreen
When the wire color is striped, the base color is given first, followed by the stripe color as
shown below:
Example: L/W = Blue with White Stripe
15 Option description This shows a description of the option abbreviationused on the page.
16 SwitchThis shows that continuity exists between terminals 1 and 2 when the switchis in the A
position. Continuity exists between terminals 1 and 3 when the switch is inthe B posi-
tion.
17 Assembly parts Connector terminal in component shows that it is a harness incorporated assembly.
18 Cell codeThis identifies each page of the wiring diagram by section, system and wiring diagram
page number.
19 Current flow arrowArrow indicates electric current flow, especially where the direction ofstandard flow (ver-
tically downward or horizontally from left to right) is difficult to follow.
A double arrow “
” shows that current can flow in either direction depending on cir-
cuit operation.
HOW TO READ WIRING DIAGRAMS
Description
GI-14

Number Item Description
20 System branchThis shows that the system branches to another system identified by cell code (section
and system).
21 Page crossingThis arrow shows that the circuit continues to another page identified by cell code.
The C will match with the C on another page within the system other than the next or
preceding pages.
22 Shielded line The line enclosed by broken line circle shows shield wire.
23Component box in
wave lineThis shows that another part of the component is also shown on another page (indicated
by wave line) within the system.
24 Component name This shows the name of a component.
25 Connector numberThis 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-556, “Main
Harness”. A coordinate grid is included for complex harnesses to aid in locating connec-
tors.
26 Ground (GND)The line spliced and grounded under wire color shows that ground line is spliced at the
grounded connector.
27 Ground (GND)This shows the ground connection. For detailed ground distribution information, refer to
EL-24, “GROUND DISTRIBUTION”.
28 Connector viewsThis area shows the connector faces of the components in the wiring diagramon the
page.
29 Common componentConnectors enclosed in broken line show that these connectors belong to thesamecom-
ponent.
30 Connector colorThis shows a code for the color of the connector. For code meaning, refer to wire color
codes, Number 14 of this chart.
31Fusible link and fuse
boxThis 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 flow in, and the shaded square shows current flow out.
32 Reference areaThis shows that more information on the Super Multiple Junction (SMJ), Electrical Units,
exists at the end of the manual. Refer to GI-20 for details.
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HOW TO READ WIRING DIAGRAMS
Description (Cont’d)
GI-15

SGI364
CONNECTOR SYMBOLS=NJGI0003S0201Most 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.
Certain systems and components, especially those related to
OBD, may use a new style slide-locking type harness connec-
tor. For description and how to disconnect, refer to EL-7, “HAR-
NESS CONNECTOR”.
SGI363
Male and female terminals
Connector guides for male terminals are shown in black and
female terminals in white in wiring diagrams.
HOW TO READ WIRING DIAGRAMS
Description (Cont’d)
GI-16

SGI862-A
DETECTABLE LINES AND NON-DETECTABLE LINESNJGI0003S0205In some wiring diagrams, two kinds of lines, representing wires,
with different weight are used.
A line with regular weight (wider line) represents a “detectable
line for DTC (Diagnostic Trouble Code)”. A “detectable line for
DTC” is a circuit in which ECM can detect its malfunctions with
the on board diagnostic system.
A line with less weight (thinner line) represents a “non-detect-
able line for DTC”. A “non-detectable line for DTC” is a circuit
in which ECM cannot detect its malfunctions with the on board
diagnostic system.
HOW TO READ WIRING DIAGRAMS
Description (Cont’d)
GI-18

NJGI0005
Work FlowNJGI0005S01
SGI838
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 diagnoses materials together including:
POWER SUPPLY ROUTING
System Operation Descriptions
Applicable Service Manual Sections
Check for any Service Bulletin.
Identify where to begin diagnoses based upon your knowledge of the system operation and the cus-
tomer 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 inadvertently created a new incident during your diagnoses or repair steps.
HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Work Flow
GI-22

Incident Simulation TestsNJGI0005S02INTRODUCTIONNJGI0005S0201Sometimes 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
Diagnoses. 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 VIBRATIONNJGI0005S0202The 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.Gentlyshake each connec-
tor and harness while monitoring the system for the incident you
are trying to duplicate. This test may indicate a loose or poor elec-
trical connection.
Hint
Connectors can be exposed to moisture. It is possible to get a thin
film of corrosion on the connector terminals. 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
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HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests
GI-23

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.
SGI842
HEAT SENSITIVENJGI0005S0203The 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 60°C (140°F).If incident occurs
while heating the unit, either replace or properly insulate the com-
ponent.
SGI843
FREEZINGNJGI0005S0204The customer may indicate the incident goes away after the car
warms up (winter time). The cause could be related to water freez-
ing somewhere in the wiring/electrical system.
There are two methods to check for this. The first is to arrange for
the owner to leave his car overnight. Make sure it will get cold
enough to demonstrate his complaint. Leave the car parked out-
side overnight. In the morning, do a quick and thorough diagnoses
of those electrical components which could be affected.
HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont’d)
GI-24

The second method is to put the suspect component into a freezer
long enough for any water to freeze. Reinstall the part into the car
and check for the reoccurrence of the incident. If it occurs, repair
or replace the component.
SGI844
WATER INTRUSIONNJGI0005S0205The incident may occur only during high humidity or in rainy/snowy
weather. In such cases the incident could be caused by water
intrusion on an electrical part. This can be simulated by soaking the
car or running it through a car wash.
Do not spray water directly on any electrical components.
SGI845
ELECTRICAL LOADNJGI0005S0206The incident may be electrical load sensitive. Perform diagnoses
with all accessories (including A/C, rear window defogger, radio,
fog lamps) turned on.
COLD OR HOT START UPNJGI0005S0207On some occasions an electrical incident may occur only when the
car is started cold. Or it may occur when the car is restarted hot
shortly after being turned off. In these cases you may have to keep
the car overnight to make a proper diagnoses.
Circuit InspectionNJGI0005S03INTRODUCTIONNJGI0005S0301In general, testing electrical circuits is an easy task if it is
approached in a logical and organized method. Before beginning
it is important to have all available information on the system to be
tested. Also, get a thorough understanding of system operation.
Then you will be able to use the appropriate equipment and follow
the correct test procedure.
You may have to simulate vehicle vibrations while testing electrical
components.Gently shakethe wiring harness or electrical com-
ponent to do this.
OPEN A circuit is open when there is no continuity through a section of
the circuit.
SHORT There are two types of shorts.
SHORT CIRCUIT When a circuit contacts another circuit
and causes the normal resistance to
change.
SHORT TO GROUND When a circuit contacts a ground source
and grounds the circuit.
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HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont’d)
GI-25