Nissan Leaf. Manual - part 710

GI-52

< BASIC INSPECTION >

SERVICE INFORMATION FOR ELECTRICAL INCIDENT

• An enlarged contact spring of a terminal may create intermittent signals in the circuit.

• If the intermittent open circuit occurs, follow the procedure below to inspect for open wires and enlarged con-

tact spring of female terminal.

1. Assemble a male terminal and approx. 10 cm (3.9 in) of wire.

NOTE:

Use a male terminal which matches the female terminal.

2. Disconnect the suspected faulty connector and hold it terminal

side up.

3. While holding the wire of the male terminal, try to insert the male

terminal into the female terminal.

CAUTION:

Never force the male terminal into the female terminal with

your hands.

4. While moving the connector, check whether the male terminal

can be easily inserted or not.

• If the male terminal can be easily inserted into the female ter-

minal, replace the female terminal.

Waterproof Connector Inspection 

If water enters the connector, it can short interior circuits. This may lead to intermittent problems.

Check the following items to maintain the original waterproof characteristics.

RUBBER SEAL INSPECTION

SEL270V

SEL271V

SEL272V

SEL273V

SERVICE INFORMATION FOR ELECTRICAL INCIDENT

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• Most waterproof connectors are provided with a rubber seal

between the male and female connectors. If the seal is missing,

the waterproof performance may not meet specifications.

• The rubber seal may come off when connectors are disconnected.

Whenever connectors are reconnected, make sure the rubber seal

is properly installed on either side of male or female connector.

WIRE SEAL INSPECTION

• The wire seal must be installed on the wire insertion area of a

waterproof connector. Be sure that the seal is installed properly.

Terminal Lock Inspection 

Check for unlocked terminals by pulling wire at the end of connector.

An unlocked terminal may create intermittent signals in the circuit.

Intermittent Incident

INFOID:0000000010122932

DESCRIPTION

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 fol-

lowing 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 following illustra-

tion.

Connector & Harness

Determine which connectors and wiring harness would affect the electrical system you are inspecting. Gently

shake each connector and harness while monitoring the system for the incident you are trying to duplicate.

This test may indicate a loose or poor electrical connection.

Hint

Connectors can be exposed to moisture. It is possible to get a thin film of corrosion on the connector termi-

nals. A visual inspection may not reveal this without disconnecting the connector. If the problem occurs inter-

mittently, 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.

Sensor & Relay

Gently apply a slight vibration to sensors and relays in the system you are inspecting.

SEL275V

SEL330V

GI-54

< BASIC INSPECTION >

SERVICE INFORMATION FOR ELECTRICAL INCIDENT

This test may indicate a loose or poorly mounted sensor or relay.

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 integrity of ground connections. (Refer to Ground

Inspection described later.) First check that the system is properly grounded. Then check for loose connection

by gently shaking the 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. Vehi-

cle vibration can aggravate 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 possible damage or

pinching.

HEAT SENSITIVE

• The customer's concern 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.

CAUTION:

Never heat components above 60

°C (140°F).

• If incident occurs while heating the unit, either replace or properly

insulate the component.

FREEZING 

• The 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. Check it will get cold enough

to demonstrate his complaint. Leave the car parked outside over-

night. In the morning, do a quick and thorough diagnosis of those

electrical components which could be affected.

• 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.

WATER INTRUSION

SGI839

SGI842

SGI843

SERVICE INFORMATION FOR ELECTRICAL INCIDENT

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The incident may occur only during high humidity or in rainy/snowy

weather. In such cases the incident could be caused by water intru-

sion on an electrical part. This can be simulated by soaking the car

or running it through a car wash.

CAUTION:

Never spray water directly on any electrical components.

ELECTRICAL LOAD 

The incident may be electrical load sensitive. Perform diagnosis with

all accessories (including A/C, rear window defogger, radio, fog

lamps) turned on.

COLD OR HOT START UP 

On 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 diagnosis.

Circuit Inspection

INFOID:0000000010122933

DESCRIPTION 

• In 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 thor-

ough 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 shake the wiring

harness or electrical component to do this.

TESTING FOR “OPENS” IN THE CIRCUIT

SGI844

SGI845

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.