1998 NISSAN PATROL check engine

ELECTRICAL SYSTEM
SECTION
EL
When you read wiring diagrams:
+Read GI section, ``HOW TO READ WIRING DIAGRAMS''.
When you perform trouble diagnoses, read GI section, ``HOW TO FOLLOW FLOW
CHART IN TROUBLE DIAGNOSES'' and ``HOW TO PERFORM EFFICIENT DIAGNOSIS
FOR AN ELECTRICAL INCIDENT''.
+Check for any service bulletins before servicing the vehicle.
CONTENTS
PRECAUTIONS...............................................................1
Supplemental Restraint System (SRS) ``AIR
BAG'' and ``SEAT BELT PRE-TENSIONER''...............1
HARNESS CONNECTOR................................................2
Description ...................................................................2
STANDARDIZED RELAY................................................3
Description ...................................................................3
POWER SUPPLY ROUTING...........................................5
Schematic ....................................................................5
Wiring Diagram Ð POWER Ð....................................6
Fuse ...........................................................................14
Fusible Link................................................................14
Circuit Breaker Inspection .........................................14
GROUND DISTRIBUTION/LHD MODELS....................15
Engine Room Harness ..............................................15
Main Harness.............................................................19
Body Harness ............................................................22
Body No. 2 Harness ..................................................23
Back Door and Rear Window Defogger Harness .....24
Room Lamp Harness.................................................25
GROUND DISTRIBUTION/RHD MODELS...................26
Engine Room Harness ..............................................26
Main Harness.............................................................30
Body Harness ............................................................33
Body No. 2 Harness ..................................................34
Back Door and Rear Window Defogger Harness .....35
Room Lamp Harness.................................................36
BATTERY.......................................................................37
How to Handle Battery ..............................................37
Battery Test and Charging Chart ...............................40
Service Data and Speci®cations (SDS).....................44
STARTING SYSTEM.....................................................45
Wiring Diagram Ð START Ð ....................................45Trouble Diagnoses.....................................................46
Construction ...............................................................47
Removal and Installation ...........................................47
Inspection...................................................................47
Assembly ...................................................................50
Service Data and Speci®cations (SDS).....................51
CHARGING SYSTEM....................................................52
Wiring Diagram Ð CHARGE Ð ................................52
Trouble Diagnoses.....................................................53
Construction ...............................................................54
Removal and Installation ...........................................54
Disassembly...............................................................54
Inspection...................................................................55
Assembly ...................................................................56
Service Data and Speci®cations (SDS).....................56
COMBINATION SWITCH...............................................57
Check .........................................................................57
Replacement ..............................................................58
STEERING SWITCH......................................................59
Check .........................................................................59
HEADLAMP Ð Conventional Type Ð........................61
Wiring Diagram Ð H/LAMP Ð ..................................61
Trouble Diagnoses.....................................................62
Bulb Replacement .....................................................63
Aiming Adjustment .....................................................63
HEADLAMP Ð Daytime Light System Ð..................65
System Description ....................................................65
Wiring Diagram Ð DTRL Ð ......................................67
Trouble Diagnoses.....................................................69
Bulb Replacement .....................................................69
Aiming Adjustment .....................................................69
HEADLAMP Ð Headlamp Aiming Control Ð............70
System Description ....................................................70
EL

CAUTION:
If it becomes necessary to start the engine with a booster bat-
tery and jumper cables,
a. Use a 12-volt booster battery.
b. After connecting battery cables, ensure that they are
tightly clamped to battery terminals for good contact.
c. Never add distilled water through the hole used to check
speci®c gravity.
How to Handle Battery
METHODS OF PREVENTING OVER-DISCHARGE
The following precautions must be taken to prevent over-discharg-
ing a battery.
+The battery surface (particularly its top) should always be kept
clean and dry.
+The terminal connections should be clean and tight.
+At every routine maintenance, check the electrolyte level.
This also applies to batteries designated as ``low maintenance''
and ``maintenance-free''.
+When the vehicle is not going to be used over a long period of
time, disconnect the negative battery terminal.
+Check the charge condition of the battery.
Periodically check the speci®c gravity of the electrolyte. Keep
a close check on charge condition to prevent over-discharge.
CHECKING ELECTROLYTE LEVEL
WARNING:
Do not allow battery ¯uid to come in contact with skin, eyes,
fabrics, or painted surfaces. After touching a battery, do not
touch or rub your eyes until you have thoroughly washed your
hands. If acid contacts eyes, skin or clothing, immediately
¯ush with water for 15 minutes and seek medical attention.
MEL040F
MEL041F
MEL042F
BATTERY
EL-37

Trouble Diagnoses
If any abnormality is found, immediately disconnect battery negative terminal.
Starter does not stop.cReplace magnetic switch.
Engine does not start.
Does engine turn by cranking?
No
cYe s
Does engine turn normally?
No (Turns slowly.)
cYe s
Check ignition/fuel system.
Check battery as follows:
+Charging condition
+Terminal connections
+Terminal corrosion
NG
cOK
Repair starter motor.
jA
Does starter motor turn?
No
cYe s
Does gear shaft turn?
No
cYe s
Check pinion clutch.
Check reduction gear, armature
and gear shaft.
Check fuse and fusible link.
OK
cNG
Replace.
Check battery as follows:
+Charging condition
+Terminal connections
+Terminal corrosion
OKj
A
cNG
+Charge battery.
+Repair connections and corro-
sion of battery terminals.
Check starting system wiring.
OK
cNG
Repair.
Does magnetic switch operation
sound occur?
Ye s
cNo
Replace magnetic switch.
Check condition of pinion and ring
gear mesh.
NG
cOK
Does starter turn under no load by
connecting wires as follows?
SEL009Z
cYe s
Replace magnetic switch.
+Adjust pinion movement.
+Check pinion moving mecha-
nism.
+Check ring gear.cNo
Repair starter motor.
.
.
.
.
.
.
.
.
.
.
.
.
STARTING SYSTEM
EL-46

Trouble Diagnoses
Before conducting an alternator test, make sure that the battery is fully charged. A 30-volt voltmeter and suit-
able test probes are necessary for the test. The alternator can be checked easily by referring to the Inspec-
tion Table.
+Before starting, inspect the fusible link.
+Use fully charged battery.
WITH IC REGULATOR
Check the fol-
lowing:
+Warning
lamp bulb
+Fuse for
warning lamp
Ignition switch
``ON''Warning lamp
``OFF''Disconnect connector (S, L) and
ground L harness side.Warning lamp
``OFF''
Warning lamp
``ON''Damaged IC
regulator.
Replace.
Warning lamp
``ON''
Engine start.
Engine speed:
1,500 rpmWarning lamp
``ON''Check the following:
+Drive belt
+Fuse for S terminal
+Connector (S, L terminal) con-
nectionEngine idlingWarning lamp
``OFF''OK
Warning lamp
``ON''
Warning lamp
``OFF''OKEngine speed:
1,500 rpm
(Measure B
terminal volt-
age)More than
15.5VDamaged IC
regulator.
Replace.
No generationField circuit is
open.
Warning lamp: ``CHARGE'' warning lamp in combination meter
Note:
+If the inspection result is OK even though the charging system is malfunctioning, check the B ter-
minal connection. (Check the tightening torque.)
+When ®eld circuit is open, check condition of rotor coil, rotor slip ring and brush. If necessary,
replace faulty parts with new ones.
MALFUNCTION INDICATOR
The IC regulator warning function activates to illuminate ``CHARGE'' warning lamp, if any of the following
symptoms occur while alternator is operating:
+Excessive voltage is produced.
+No voltage is produced.
CHARGING SYSTEM
EL-53

SYMPTOM CHART
Symptom chart 1 (Malfunction is indicated in Diagnosis mode)
Symptom Possible causes Repair order
Speedometer and/or odo/trip
meter indicate(s) malfunction
in Diagnosis mode.+Speedometer (Uni®ed meter control unit)+Replace speedometer (uni®ed meter control unit).
Multiple meter/gauge indicate
malfunction in Diagnosis
mode.
One of tachometer/fuel gauge/
water temp. gauge indicates
malfunction in Diagnosis
mode.+Meter/Gauge
+Speedometer (Uni®ed meter control unit)1. Check resistance of meter/gauge indicating malfunction. If
the resistance is NG, replace the meter/gauge. Refer to
``METER/GAUGE RESISTANCE CHECK'', EL-114.
2. If the resistance is OK, replace speedometer (uni®ed meter
control unit).
Symptom chart 2 (No malfunction is indicated in Diagnosis mode)
Symptom Possible causes Repair order
Speedometer and odo/trip
meter are malfunctioning.1. Sensor
- Speedometer, Odo/Trip meter
2. FPC connector
3. Speedometer (Uni®ed meter control unit)1. Check vehicle speed sensor.
INSPECTION/VEHICLE SPEED SENSOR (Refer to EL-112.)
2. Check FPC connector. Refer to ``Flexible Print Circuit
(FPC)'', EL-109.
3. Replace speedometer (uni®ed meter control unit).
Multiple meter/gauge are mal-
functioning. (except
speedometer, odo/trip meter)1. FPC connector
2. Speedometer (Uni®ed meter control unit)1. Check FPC connector. Refer to ``Flexible Print Circuit
(FPC)'', EL-109.
2. Replace speedometer (uni®ed meter control unit).
One of tachometer/fuel gauge/
water temp. gauge is malfunc-
tioning.1. Sensor/Engine revolution signal
- Tachometer
- Fuel gauge
- Water temp. gauge
2. FPC connector
3. Speedometer (Uni®ed meter control unit)1. Check the sensor for malfunctioning meter/gauge.
INSPECTION/ENGINE REVOLUTION SIGNAL (Refer to
EL-113.)
INSPECTION/FUEL TANK GAUGE (Refer to EL-113.)
INSPECTION/THERMAL TRANSMITTER (Refer to EL-114.)
2. Check FPC connector. Refer to ``Flexible Print Circuit
(FPC)'', EL-109.
3. Replace speedometer (uni®ed meter control unit).
Before starting trouble diagnoses above, perform PRELIMINARY CHECK, EL-110.
POWER SUPPLY AND GROUND CIRCUIT CHECK
Power supply circuit check
Terminals Ignition switch position
Å@OFF ACC ON
j
33GroundBattery
voltageBattery
voltageBattery
voltage
j
9Ground 0V 0VBattery
voltage
If NG, check the following.
+7.5A fuse [No.
24, located in fuse block (J/B)]
+10A fuse [No.
28, located in fuse block (J/B)]
+Harness for open or short between fuse and combination meter
SEL419V
METER AND GAUGES
Trouble Diagnoses (Cont'd)
EL-111

INSPECTION/ENGINE REVOLUTION SIGNAL
Engine Check itemTerminals
ExplanationÅ@
RD28 (Injec-
tion)DC voltagej
44GroundHigher rpm = Higher volt-
age
Lower rpm = Lower volt-
age
Voltage should change
with rpm.
Engine Check item
TB45E, RD28
(Injection)+Harness for open or short and connection
INSPECTION/FUEL TANK GAUGE (MAIN)
CHECK GROUND CIRCUIT FOR FUEL
TANK GAUGE UNIT.
Check harness continuity between fuel
tank gauge unit terminalj
2and ground.
Continuity should exist.
OK
cNG
Repair harness or connec-
tor.
CHECK GAUGE UNITS.
Refer to ``FUEL TANK GAUGE UNIT
CHECK'' (EL-115).
OK
cNG
Repair or replace.
Refer to FE section.
CHECK HARNESS FOR OPEN OR
SHORT.
1. Disconnect combination connector and
fuel tank gauge unit connector.
2. Check continuity between combination
meter terminalj
46and fuel tank gauge
unit terminalj
1.
Continuity should exist.
3. Check continuity between combination
meter terminalj
46and ground.
Continuity should not exist.
OK
cNG
Repair harness or connec-
tor.
Fuel tank gauge is OK.
SEL423V
SEL461V
SEL424V
SEL425V
.
.
.
METER AND GAUGES
Trouble Diagnoses (Cont'd)
EL-113

Trouble Diagnoses
PRELIMINARY CHECK FOR THERMOMETER
Turn the ignition key switch to the ``ACC''
position.
Cool down the ambient air temperature
sensor with water or ice, so that the indi-
cated temperature falls.
Does the indicated temperature fall?
Ye s
cNo
The system is malfunction-
ing..1
Leave the vehicle for 10 minutes, so that
the indicated temperature rises.
With the ignition key in the ``ACC''
position, disconnect and reconnect the
ambient air temperature sensor connector.
Does the indicated temperature rise?
Ye s
cNo
The system is malfunction-
ing..1
The system is OK.
.1: Check the system following ``INSPECTION/COMPASS AND THERMOM-
ETER''.
INSPECTION/COMPASS AND THERMOMETER
Symptom Possible causes Repair order
No display at all 1. 7.5A fuse
2. Ground circuit
3. Compass and thermometer1. Check 7.5A fuse [No.
9, located in fuse block (J/B)].
Turn the ignition switch ON and verify that battery positive
voltage is at terminalj
2of compass and thermometer.
2. Check ground circuit for compass and thermometer.
3. Replace compass and thermometer.
Forward direction indication
slips off the mark or incorrect.1. In manual correction mode
(Bar and display vanish.)
2. Zone variation change is not
done.1. Drive the vehicle and turn at an angle of 90É.
2. Perform the zone variation change.
Compass reading remains
unchanged.1. Vehicle speed sensor is not
entered.
2. Compass and thermometer1. Check harness for open or short between combination meter
terminalj
26and compass and thermometer terminalj8.
2. Replace compass and thermometer.
Displays wrong temperature
when ambient temperature is
between þ30ÉC (þ20ÉF) and
55ÉC (130ÉF). (See NOTE)1. Check operation
2. Ambient air temperature
sensor circuit
3. Vehicle speed sensor is not
entered.
4. Ambient air temperature
sensor
5. Compass and thermometer1. Perform preliminary check shown below.
2. Check harness for open or short between ambient air tem-
perature sensor and compass and thermometer.
3. Check harness for open or short between combination meter
terminalj
26and compass and thermometer terminalj8.
4. Replace ambient air temperature sensor.
5. Replace compass and thermometer.
NOTE:
+When the outside temperature is between 55ÉC (130ÉF) and 70ÉC (158ÉF), the display shows 55ÉC
(130ÉF). When the outside temperature is lower than þ30ÉC (þ20ÉF) or higher than 70ÉC (158ÉF), the
display shows only ``- - -''.
+The indicated temperature on the thermometer is not readily affected by engine heat. It changes
only when one of the following conditions (shown on next page) is present.
.
.
.
.
.
.
COMPASS AND THERMOMETER
EL-118

Electrical Components Inspection
FUEL WARNING LAMP SENSOR CHECK
+It will take a short time for the bulb to light.
NOTE: Inspection for sub fuel warning lamp sensor is the
same as for fuel warning lamp sensor.
OIL PRESSURE SWITCH CHECK
Oil pressure
kPa (bar, kg/cm2, psi)Continuity
Engine startMore than 10 - 20
(0.10 - 0.20, 0.1 - 0.2,1-3)NO
Engine stopLess than 10 - 20
(0.10 - 0.20, 0.1 - 0.2,1-3)YES
Check the continuity between the terminals of oil pressure switch
and body ground.
DIODE CHECK
+Check continuity using an ohmmeter.
+Diode is functioning properly if test results are as shown in the
®gure at left.
NOTE: Speci®cation may vary depending on the type of tester.
Before performing this inspection, be sure to refer to
the instruction manual for the tester to be used.
+Diodes for warning lamps are built into the combination meter
printed circuit.
MEL828F
MEL425F
CEL520
CEL740
WARNING LAMPS
EL-134