1995 NISSAN ALMERA N15 bulb

ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION
\ I/

'~/'

- CHECK-

/
.......

/ I\

SEF051P
Malfunction
Indicatorlamp(Mil)

1. The malfunction indicatorlampwilllight upwhen theigni-
tion switch isturned ONwithout theengine running. Thisis
a bulb check.
• Ifthe malfunction indicatorlampdoes notlight up,refer to
EL section ("WARNING LAMPSANDCHIME") orsee

EC-370.

2. When theengine isstarted, themalfunction indicatorlamp
should gooff.

Condition Diagnostic
Diagnostic
Test Mode I TestMode II
Engine
stopped BULBCHECK SELF-DIAGNOSTIC
Ignition

0
RESULTS
switch in
"ON" posi-
tion Engine
HEATEDOXYGEN
~ running
MALFUNCTION
SENSORMONI-

ID
WARNING
TOR
EC-250

ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION
Malfunction IndicatorLamp(MIL)(Cont'd)
HOW TOSWITCH DIAGNOSTIC TESTMODES
~ Turnignition switch"ON".(Donot
~ startengine.)
~
•SWitching thediagnostic testmode isnot possible when
the engine isrunning.
• When ignition switchisturned offduring diagnosis, power
to ECM willdrop afterapprox. 1second.
The diagnosis willautomatically returntoDiagnostic Test
Mode
I.

Diagnostic
TestMode I- BULB CHECK

1

~yW~r
~-~

Data linkconnector forCONSULT
(Connect CHKandIGNterminals
with asuitable harness.)
Wait atleast 2seconds.
CHKIGN

~J/~l
~-~

Data linkconnector forCONSULT
(Disconnect CHKandIGNterminals
with asuitable harness.)
DIAGNOSTIC TESTMODE II
- SELF-DIAGNOSTIC RESULTS

~

f!i~:~~-~
w;ir

l~mv
-~

Data linkconnector forCONSULT
(Connect CHKandIGN terminals
with asuitable harness.)
Wait atleast 2seconds.

~

~/~~N
~-~

Data linkconnector forCONSULT
(Disconnect CHKandIGNterminals
with asuitable harness.)
I

Startengine.
Start engine. Diagnostic
TestMode I-
MALFUNCTION WARNING
Diagnostic TestMode II
- HEATED OXYGEN
SENSOR MONITOR
•

EC-251

ON-BOARDDIAGNOSTIC SYSTEMDESCRIPTION ~

Malfunction IndicatorLamp(MIL)(Cont'd)

DIAGNOSTIC TESTMODE I-BULB CHECK

In this mode, theMALFUNCTION INDICATORLAMPonthe instrument panelshould stayON.If
it
remains
OFF, check thebulb. Refer toEL section ("WARNING LAMPSANDCHIME") orsee EC-370.

DIAGNOSTIC TESTMODE I-MALFUNCTION WARNING
MALFUNCTION INDICATORLAMP
ON
OFF Condition
Engine coolant temperature sensorcircuitmalfunction isdetected, orthe ECM's CPU
is malfunctioning.
No malfunction.

• These Diagnostic TroubleCodeNumbers areclarified inDiagnostic TestMode II(SELF-DIAGNOS-
TIC RESULTS).

DIAGNOSTIC TESTMODE II-SELF-DIAGNOSTIC RESULTS

In this mode, adiagnostic troublecodeisindicated bythe number ofblinks ofthe MALFUNCTION INDI-
CATOR LAMPasshown below.

Example: Diagnostic troublecodeNo.12and No.43

0.6 0.3

ON
1111

OFF ~
0.9 0.3
0.6

--I~
2.1 0.6
0.9
0.3

Unit:second
Diagnostic troublecodeNo.12 Diagnostic
troublecodeNo.43

AEC490
• SELF-DIAG RESULTS.
0

FAILURE DETECTED TIME
NATS MALFUNCTION

0

I
ERASE

II
PRINT

I

SEF288Q

Long
(0.6second) blinkingindicates thenumber often digits, andshort (0.3second) blinkingindicates
the number ofsingle digits.Forexample, themalfunction indicatorlampblinks 4times forabout 2.5
seconds (0.6secx4times) andthen itblinks threetimes forabout 1second (0.3sec x3 times). This
indicates theDTC "43" andrefers tothe malfunction ofthe throttle position sensor.
In this way, allthe detected malfunctions areclassified bytheir diagnostic troublecodenumbers. The
DTC "55" refers tono malfunction. (SeeDIAGNOSTIC TROUBLECODECHART, refertoEC-268.)

HOW TOERASE DIAGNOSTIC TESTMODE II(Self-diagnostic results)

The diagnostic troublecodecanbeerased fromthebackup memory inthe ECM when thediagnostic
test mode ischanged fromDiagnostic TestMode IIto Diagnostic TestMode
I.
(Refer to"HOW TO
SWITCH DIAGNOSTIC TESTMODES" onprevious page.)
• Ifthe battery terminal isdisconnected, thediagnostic troublecodewillbelost from thebackup
memory within24hours.
• Becareful nottoerase thestored memory beforestarting- troublediagnoses.
• Ifthe MIL blinks or"NATS MALFUNCTION" isdisplayed on
"SELF-OIAG RESULTS"screen,perform self-diagnostic
results modewithCONSULT usingNATS program card
(NA TS-E940). RefertoEL section.
• Confirm noself-diagnostic resultsofNATS isdisplayed
before touching "ERASE" in"SELF-DiAG RESULTS"mode
with CONSULT.
• When replacing ECM,inltialisation ofNATS V2.0system and
registration ofall NATS V2.0 Ignition keyIDsmust becar-
ried outwith CONSULT usingNATS program card(NATS-
E940).
Therefore, besure toreceive allkeys from vehicle owner.
Regarding theprocedures ofNATS initialisation andNATS
ignition key
10
registration, refertoCONSULT operation
manual, NATS V2.0.

EC-252

TROUBLEDIAGNOSES ~
Quick-glow System(Cont'd)

• If
NG.
check component partsandtheir related harness
according tothe following chart.

Parts which should bechecked
Terminal Fuse Glowin-
No. Battery IFusible Glow
Key-in Ignition
dicatorHarness
link relay
switch switch
bulb

@
XX
X

@
X
X X X

@
XX
X X

@,@
XX XX

@
XX X
X X

@
X
X XX

COMPONENT INSPECTION
Glow relay

1. Check relayforcoil continuity.

Continuity shouldexist.

2. Check relayforproper operation.

Coil voltage Continuity
Contactpoint

OV
NoOFF

12V
Yes ON
•

Ohmmeter SEC5648
SEF630K Glow
plug

1. Remove glowplugconnecting plate.
2. Check eachglow plugforcontinuity.

Continuity shouldexist:
Approximately 0.650

• IfNG, replace glowplug.

EC-397

HOWTOPERFORM EFFICIENT DIAGNOSIS FORANELECTRICAL INCIDENT
Circuit Inspection (Cont'd)
VOLTAGE DROPTESTS

Voltage droptests areoften usedtofind components orcircuits whichhaveexcessive resistance. A
voltage dropinacircuit iscaused byaresistance
whenthecircuit isin operation.

Check thewire inthe illustration. Whenmeasuring resistancewithohmmeter, contactbyasingle strand
of wire willgive reading of0ohms. Thiswould indicate agood circuit. Whenthecircuit operates, this
single strand ofwire isnot able tocarry thecurrent. Thesingle strand willhave ahigh resistance tothe
current. Thiswillbepicked upasaslight voltage drop.
Unwanted resistance canbecaused bymany situations asfollows:
Undersized wiring(single strandexample)
Corrosion onswitch contacts
Loose wireconnections orsplices.

If
repairs areneeded alwaysusewire thatisof the same orlarger gauge.

Measuring voltagedrop-Accumulated method

1. Connect thevoltmeter acrosstheconnector orpart ofthe circuit youwant tocheck. Thepositive lead
of the voltmeter shouldbecloser topower andthenegative leadcloser toground.
2. Operate thecircuit.
3. The voltmeter willindicate howmany voltsarebeing usedto"push" current through thatpart ofthe
circuit.

Note inthe illustration thatthere isan excessive 4.1volt drop between thebattery andthebulb.
Symptom: Dimbulb orno operation
Switch Connectionwith
high resistance

l ;

--

------------------~

--
\

~~~~ I

-, OVI

11.9V:
'I

I
Load)

--

12V
DMM
Battery
Ground

o

(zero) ohm
resistance
between switch
and bulb

t
•
__
Ground
SGI848
Measuring voltagedrop-Step bystep

The step bystep method ismost useful forisolating excessive dropsinlow voltage systems (suchas
those in"Computer ControlledSystems").
Circuits inthe "Computer ControlledSystem"operateonvery lowamperage.
The (Computer Controlled) systemoperations canbeadversely affectedbyany variation inresistance
in the system. Suchresistance variationmaybecaused bypoor connection, improperinstallation,
improper wiregauge orcorrosion.
The step bystep voltage droptestcan identify acomponent orwire withtoomuch resistance.

GI-26