2001 NISSAN ALMERA N16 bulb

strand will have a high resistance to the current. This will be picked
up as a slight voltage drop.
Unwanted resistance can be caused by many situations as follows:
+Undersized wiring (single strand example)
+Corrosion on switch contacts
+Loose wire connections or splices.
If repairs are needed always use wire that is of the same or larger
gauge.
Measuring Voltage Drop Ð Accumulated Method
1) Connect the voltmeter across the connector or part of the cir-
cuit you want to check. The positive lead of the voltmeter
should be closer to power and the negative lead closer to
ground.
2) Operate the circuit.
3) The voltmeter will indicate how many volts are being used to
ªpushº current through that part of the circuit.
Note in the illustration that there is an excessive 4.1 volt drop
between the battery and the bulb.
SGI974
Measuring Voltage Drop Ð Step by Step
The step by step method is most useful for isolating excessive
drops in low voltage systems (such as those in ªComputer Con-
trolled Systemsº).
Circuits in the ªComputer Controlled Systemº operate on very low
amperage.
The (Computer Controlled) system operations can be adversely
affected by any variation in resistance in the system. Such resis-
tance variation may be caused by poor connection, improper
installation, improper wire gauge or corrosion.
The step by step voltage drop test can identify a component or wire
with too much resistance.
HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Circuit Inspection (Cont'd)
GI-28

SEF543X
NATS (Nissan Anti-theft System)NJEC0591+If the security indicator lights up with the ignition switch
in the ªONº position or ªNATS MALFUNCTIONº is dis-
played on ªSELF-DIAG RESULTSº screen, perform self-
diagnostic results mode with CONSULT-II using NATS pro-
gram card. Refer to NATS (Nissan Anti-Theft System) in EL
section.
+Confirm no self-diagnostic results of NATS is displayed
before touching ªERASEº in ªSELF-DIAG RESULTSº
mode with CONSULT-II.
+When replacing ECM, initialization of NATS system and
registration of all NATS ignition key IDs must be carried
out with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner.
Regarding the procedure of NATS initialization and NATS
ignition key ID registration, refer to CONSULT-II operation
manual, NATS.
Malfunction Indicator (MI)
DESCRIPTIONNJEC0032
SAT652J
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without the engine running. This is a bulb check.
+If the MI does not light up, refer to EL-107, ªWARNING LAMPSº or see EC-488.
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnostic System FunctionNJEC0032S01The on board diagnostic system has the following four functions.
Diagnostic Test Mode I
1. BULB CHECK:
This function checks the MI bulb for damage (blown, open circuit, etc.).
If the MI does not come on, check MI circuit and ECM test mode selector. (See the following page.)
2. MALFUNCTION WARNING:
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
Diagnostic Test Mode II (If so equipped)
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
NATS (Nissan Anti-theft System)
EC-72

3. SELF-DIAGNOSTIC RESULTS:
This function allows DTCs and 1st trip DTCs to be read.
4. HEATED OXYGEN SENSOR 1 MONITOR (FRONT):
This function allows the fuel mixture condition (lean or rich), monitored by heated oxygen sensor 1 (front),
to be read.
MI Flashing without DTC
NJEC0032S0101If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM test
mode following ªHow to Switch Diagnostic Test Modesº.
How to switch the diagnostic test (function) modes, and details of the above functions are described later.
(Refer to EC-74.)
Condition Diagnostic Test Mode I Diagnostic Test Mode II
Ignition switch in ªONº position
Engine stopped
BULB CHECK SELF-DIAGNOSTIC RESULTS
Engine running
MALFUNCTION WARNINGHEATED OXYGEN SENSOR 1
MONITOR (FRONT)
The following emission-related diagnostic information is cleared when the ECM memory is erased.
1) Diagnostic trouble codes
2) 1st trip diagnostic trouble codes
3) Freeze frame data
4) 1st trip freeze frame data
5) System readiness test (SRT) codes
6) Test values
7) Distance traveled while MI is activated
8) Others
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Malfunction Indicator (MI) (Cont'd)
EC-73

Diagnostic Test Mode I Ð Bulb CheckNJEC0032S03In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the MI bulb. Refer to
EL-107, ªWARNING LAMPSº or see EC-488.
Diagnostic Test Mode I Ð Malfunction WarningNJEC0032S04
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
+These DTC numbers are clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS).
Diagnostic Test Mode II Ð Self-diagnostic Results (If so equipped)NJEC0032S05In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MI as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MI does not illuminate in diagnostic test mode
I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MI illu-
minates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are
displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These uni-
dentified codes can be identified by using the CONSULT-II or GST. A DTC will be used as an example for how
to read a code.
SEF952W
A particular trouble code can be identified by the number of four-digit numeral flashes. The ªzeroº is indicated
by the number of ten flashes. The length of time the 1000th-digit numeral flashes on and off is 1.2 seconds
consisting of an ON (0.6-second)-OFF (0.6-second) cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0 second OFF. In other words, the lat-
ter numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8 second off.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC ª0000º refers to no
malfunction. (See TROUBLE DIAGNOSIS Ð INDEX, EC-10.)
How to Erase Diagnostic Test Mode II (Self-diagnostic results)
NJEC0032S0501The DTC can be erased from the backup memory in the ECM when the diagnostic test mode is changed from
Diagnostic Test Mode II to Diagnostic Test Mode I. (Refer to ªHow To Switch Diagnostic Test Modesº, EC-74.)
+If the battery is disconnected, the DTC will be lost from the backup memory after approx. 24 hours.
+Be careful not to erase the stored memory before starting trouble diagnoses.
Diagnostic Test Mode II Ð Heated Oxygen Sensor 1 Monitor (Front) (If so equipped)NJEC0032S06In this mode, the MI displays the condition of the fuel mixture (lean or rich) which is monitored by the heated
oxygen sensor 1 (front).
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONQG
Malfunction Indicator (MI) (Cont'd)
EC-75

+Erasing the emission-related diagnostic information using CONSULT-II is easier and quicker than
switching the diagnostic test mode using the data link connector.
Malfunction Indicator (MI)
DESCRIPTIONNJEC0628
SAT652J
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without the engine running. This is a bulb check.
+If the MI does not light up, refer to EL-107, ªWARNING LAMPSº or see EC-701.
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has detected an engine system malfunction.
If MI illuminates or blinks irregularly after starting engine, water may have accumulated in fuel filter.
Drain water from fuel filter. Refer to ªWATER DRAININGº, EC-520.
On Board Diagnostic System FunctionNJEC0628S01The on board diagnostic system has the following three functions.
Diagnostic Test
ModeKEY and ENG.
StatusFunction Explanation of Function
Mode I Ignition switch in
ON position
Engine stopped
BULB CHECK This function checks the MI bulb for damage (blown,
open circuit, etc.).
If the MI does not come on, check MI circuit. (See
EC-701.)
Engine running
MALFUNCTION
WARNINGThis is a usual driving condition. When ECM detects a
malfunction, the MI will light up to inform the driver that
a malfunction has been detected.
Mode II Ignition switch in
ON position
Engine stopped
SELF-DIAGNOSTIC RESULTS This function allows DTCs to be read.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
Malfunction Indicator (MI)
EC-523

Diagnostic Test Mode I Ð Bulb CheckNJEC0628S03In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to EL-107,
ªWARNING LAMPSº or see EC-701.
Diagnostic Test Mode I Ð Malfunction WarningNJEC0628S04
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
Diagnostic Test Mode II Ð Self-diagnostic ResultsNJEC0628S05In this mode, DTC is indicated by the number of blinks of the MI as shown below.
SEF298QA
SEF162PB
Long (0.6 second) blinking indicates the two LH digits of number and short (0.3 second) blinking indicates the
two RH digits of number. For example, the MI blinks 10 times for 6 seconds (0.6 sec x 10 times) and then it
blinks three times for about 1 second (0.3 sec x 3 times). This indicates the DTC ª1003º.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC ª0505º refers to no
malfunction. (See TROUBLE DIAGNOSIS Ð INDEX, EC-492.)
How to Erase Diagnostic Test Mode II (Self-diagnostic results)NJEC0628S06The DTC can be erased from the backup memory in the ECM when the diagnostic test mode is changed from
Diagnostic Test Mode II to Diagnostic Test Mode I. (Refer to ªHow to Switch Diagnostic Test Modesº, EC-524.)
+If the battery terminal is disconnected, the DTC will be lost from the backup memory within 24
hours.
+Be careful not to erase the stored memory before starting trouble diagnoses.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONYD
Malfunction Indicator (MI) (Cont'd)
EC-525

5 RECHECK BRAKE FLUID LEVEL
Check brake fluid level in reservoir tank again.
SBR451D
Is brake fluid filled between MAX and MIN lines on reservoir tank and/or has brake fluid been contaminated?
Ye s©GO TO 6.
No©Fill up brake fluid.
6 CHECK WARNING LAMP ACTIVATION
Check warning lamp activation.
SBR759E
Does warning lamp turn on when ignition switch is turned ªONº?
Ye s©GO TO 7.
No©Check fuse, warning lamp bulb and warning lamp circuit.
7 CHECK WARNING LAMP DEACTIVATION
Check warning lamp for deactivation after engine is started.
Does warning lamp turn off when engine is started?
Ye s©GO TO 8.
No©Go to Self-diagnosis. Refer to BR-58.
8 DRIVE VEHICLE
Drive vehicle at speeds over 30 km/h (19 MPH) for at least one minute.
Does warning lamp remain off after vehicle has been driven at 30 km/h (19 MPH) for at least one minute?
Ye s©END
No©Go to Self-diagnosis. Refer to BR-58.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONABS
Preliminary Check (Cont'd)
BR-67

ELECTRICAL SYSTEM
SECTION
EL
CONTENTS
PRECAUTIONS...............................................................4
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............4
Wiring Diagrams and Trouble Diagnosis .....................4
HARNESS CONNECTOR................................................5
Description ...................................................................5
STANDARDIZED RELAY................................................7
Description ...................................................................7
POWER SUPPLY ROUTING...........................................9
Schematic ..................................................................10
Wiring Diagram - POWER - ......................................12
Inspection...................................................................22
GROUND........................................................................23
Ground Distribution ....................................................23
COMBINATION SWITCH..............................................37
Check .........................................................................37
Replacement ..............................................................38
STEERING SWITCH......................................................39
Check .........................................................................39
HEADLAMP...................................................................40
Wiring Diagram - H/LAMP -.......................................40
Trouble Diagnoses.....................................................41
Bulb Replacement .....................................................42
Aiming Adjustment .....................................................42
HEADLAMP - DAYTIME LIGHT SYSTEM -.................44
System Description ....................................................44
Schematic ..................................................................45
Wiring Diagram - DTRL - ...........................................46
Trouble Diagnoses.....................................................49
Bulb Replacement .....................................................49
Aiming Adjustment .....................................................50
HEADLAMP - HEADLAMP AIMING CONTROL -........51
Wiring Diagram - H/AIM - ..........................................51
PARKING, LICENSE AND TAIL LAMPS.....................53
Wiring Diagram - TAIL/L - ..........................................53
STOP LAMP..................................................................56
Wiring Diagram - STOP/L - .......................................56
BACK-UP LAMP............................................................58
Wiring Diagram - BACK/L - .......................................58FRONT FOG LAMP.......................................................60
Wiring Diagram - F/FOG - .........................................60
Bulb Replacement .....................................................61
Aiming Adjustment .....................................................62
REAR FOG LAMP.........................................................63
Wiring Diagram - R/FOG -.........................................63
TURN SIGNAL AND HAZARD WARNING LAMPS.....65
System Description ....................................................65
Schematic ..................................................................66
Wiring Diagram - TURN - ..........................................67
Trouble Diagnoses.....................................................70
ILLUMINATION..............................................................71
Schematic ..................................................................71
Wiring Diagram - ILL - ...............................................72
INTERIOR ROOM LAMP...............................................76
System Description/ With Interior Room Lamp
Timer ..........................................................................76
Wiring Diagram - ROOM/L -/ With Interior Room
Lamp Timer ................................................................78
Trouble Diagnoses/ With Interior Room Lamp
Timer ..........................................................................80
Wiring Diagram - ROOM/L -/ Without Timer .............86
SPOT AND TRUNK ROOM LAMPS.............................87
Wiring Diagram - INT/L - ...........................................87
METERS AND GAUGES...............................................89
Component Parts and Harness Connector
Location .....................................................................89
System Description ....................................................89
Combination Meter ....................................................91
Schematic ..................................................................92
Construction ...............................................................93
Wiring Diagram - METER - .......................................94
Combination Meter Self-Diagnosis ............................96
Trouble Diagnoses.....................................................99
Electrical Components Inspection ...........................106
WARNING LAMPS......................................................107
Schematic ................................................................107
Wiring Diagram - WARN - .......................................108
Electrical Components Inspection ........................... 112