Nissan Murano Z50 (2006 year). Manual - part 77

INDEX FOR DTC

EC-11

C

D

E

F

G

H

I

J

K

L

M

A

EC

Revision: 2006 August

2006 Murano

*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: The troubleshooting for this DTC needs CONSULT-II.
*5: When the fail-safe operations for both self-diagnoses occur at the same time, the MIL illuminates.

Alphabetical Index

NBS003F2

NOTE:

●

If DTC U1000 or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to 

EC-152, "DTC U1000, U1001 CAN COMMUNICATION LINE"

  .

●

If DTC U1010 is displayed with other DTC, first perform the trouble diagnosis for DTC U1010. Refer
to 

EC-155, "DTC U1010 CAN COMMUNICATION"

  .

P1778

1778

STEP MOTR FNC

CVT-176

P1800

1800

VIAS S/V CIRC

EC-542

P1805

1805

BRAKE SW/CIRCUIT

EC-547

P2100

2100

ETC MOT PWR

EC-552

P2101

2101

ETC FUNCTION/CIRC

EC-558

P2103

2103

ETC MOT PWR

EC-552

P2118

2118

ETC MOT

EC-564

P2119

2119

ETC ACTR

EC-569

P2122

2122

APP SEN 1/CIRC

EC-571

P2123

2123

APP SEN 1/CIRC

EC-571

P2127

2127

APP SEN 2/CIRC

EC-577

P2128

2128

APP SEN 2/CIRC

EC-577

P2135

2135

TP SENSOR

EC-584

P2138

2138

APP SENSOR

EC-591

P2A00

2A00

A/F SENSOR1 (B1)

EC-598

P2A03

2A03

A/F SENSOR1 (B2)

EC-598

DTC*

1

Items

 (CONSULT-II screen terms)

Reference page

CONSULT-II

GST*

2

ECM*

3

Items

 (CONSULT-II screen terms)

DTC*

1

Reference page

CONSULT-II

GST*

2

ECM*

3

A/F SEN1 HTR (B1)

P0031

0031

EC-161

A/F SEN1 HTR (B1)

P0032

0032

EC-161

A/F SEN1 HTR (B2)

P0051

0051

EC-161

A/F SEN1 HTR (B2)

P0052

0052

EC-161

A/F SENSOR1 (B1)

P0130

0130

EC-229

A/F SENSOR1 (B1)

P0131

0131

EC-240

A/F SENSOR1 (B1)

P0132

0132

EC-250

A/F SENSOR1 (B1)

P0133

0133

EC-260

A/F SENSOR1 (B1)

P2A00

2A00

EC-598

A/F SENSOR1 (B2)

P0150

0150

EC-229

A/F SENSOR1 (B2)

P0151

0151

EC-240

A/F SENSOR1 (B2)

P0152

0152

EC-250

A/F SENSOR1 (B2)

P0153

0153

EC-260

A/F SENSOR1 (B2)

P2A03

2A03

EC-598

EC-12

INDEX FOR DTC

Revision: 2006 August

2006 Murano

A/T TCC S/V FNCTN

P0744

0744

CVT-113

APP SENSOR

P2138

2138

EC-591

APP SEN 1/CIRC

P2122

2122

EC-571

APP SEN 1/CIRC

P2123

2123

EC-571

APP SEN 2/CIRC

P2127

2127

EC-577

APP SEN 2/CIRC

P2128

2128

EC-577

ASCD BRAKE SW

P1572

1572

EC-527

ASCD SW

P1564

1564

EC-520

ASCD VHL SPD SEN

P1574

1574

EC-535

ATF TEMP SEN/CIRC

P0710

0710

CVT-88

BRAKE SW/CIRCUIT

P1805

1805

EC-547

CAN COMM CIRCUIT

U1000

1000*

4

EC-152

CAN COMM CIRCUIT

U1001

1001*

4

EC-152

CKP SEN/CIRCUIT

P0335

0335

EC-364

CLOSED LOOP-B1

P1148

1148

EC-499

CLOSED LOOP-B2

P1168

1168

EC-499

CMP SEN/CIRC-B1

P0340

0340

EC-371

CMP SEN/CIRC-B2

P0345

0345

EC-371

COLD START CONTROL

P1421

1421

EC-518

CONTROL UNIT(CAN)

U1010

1010

EC-155

CTP LEARNING

P1225

1225

EC-514

CTP LEARNING

P1226

1226

EC-516

CVT C/U FUNCT

P1700

1700

EC-537

CYL 1 MISFIRE

P0301

0301

EC-350

CYL 2 MISFIRE

P0302

0302

EC-350

CYL 3 MISFIRE

P0303

0303

EC-350

CYL 4 MISFIRE

P0304

0304

EC-350

CYL 5 MISFIRE

P0305

0305

EC-350

CYL 6 MISFIRE

P0306

0306

EC-350

ECM

P0605

0605

EC-486

ECM BACK UP/CIRCUIT

P0603

0603

EC-482

ECT SEN/CIRC

P0117

0117

EC-209

ECT SEN/CIRC

P0118

0118

EC-209

ECT SENSOR

P0125

0125

EC-221

ENG OVER TEMP

P1217

1217

EC-502

ETC ACTR

P2119

2119

EC-569

ETC FUNCTION/CIRC

P2101

2101

EC-558

ETC MOT

P2118

2118

EC-564

ETC MOT PWR

P2100

2100

EC-552

ETC MOT PWR

P2103

2103

EC-552

EVAP GROSS LEAK

P0455

0455

EC-447

EVAP PURG FLOW/MON

P0441

0441

EC-387

Items

 (CONSULT-II screen terms)

DTC*

1

Reference page

CONSULT-II

GST*

2

ECM*

3

INDEX FOR DTC

EC-13

C

D

E

F

G

H

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EC

Revision: 2006 August

2006 Murano

EVAP SMALL LEAK

P0442

0442

EC-392

EVAP SYS PRES SEN

P0451

0451

EC-430

EVAP SYS PRES SEN

P0452

0452

EC-433

EVAP SYS PRES SEN

P0453

0453

EC-439

EVAP VERY SML LEAK

P0456

0456

EC-456

FTT SEN/CIRCUIT

P0182

0182

EC-338

FTT SEN/CIRCUIT

P0183

0183

EC-338

FTT SENSOR

P0181

0181

EC-332

FUEL LEVEL SENSOR

P0461

0461

EC-467

FUEL LEVL SEN/CIRC

P0462

0462

EC-469

FUEL LEVL SEN/CIRC

P0463

0463

EC-469

FUEL LEV SEN SLOSH

P0460

0460

EC-465

FUEL SYS-LEAN-B1

P0171

0171

EC-308

FUEL SYS-LEAN-B2

P0174

0174

EC-308

FUEL SYS-RICH-B1

P0172

0172

EC-320

FUEL SYS-RICH-B2

P0175

0175

EC-320

HO2S2 HTR (B1)

P0037

0037

EC-170

HO2S2 HTR (B1)

P0038

0038

EC-170

HO2S2 HTR (B2)

P0057

0057

EC-170

HO2S2 HTR (B2)

P0058

0058

EC-170

HO2S2 (B1)

P0137

0137

EC-273

HO2S2 (B1)

P0138

0138

EC-284

HO2S2 (B1)

P0139

0139

EC-297

HO2S2 (B2)

P0157

0157

EC-273

HO2S2 (B2)

P0158

0158

EC-284

HO2S2 (B2)

P0159

0159

EC-297

IAT SEN/CIRCUIT

P0112

0112

EC-204

IAT SEN/CIRCUIT

P0113

0113

EC-204

IAT SENSOR

P0127

0127

EC-224

INT/V TIM CONT-B1

P0011

0011

EC-157

INT/V TIM CONT-B2

P0021

0021

EC-157

INT/V TIM V/CIR-B1

P0075

0075

EC-179

INT/V TIM V/CIR-B2

P0081

0081

EC-179

IN PULY SPEED

P1715

1715

EC-538

INPUT SPD SEN/CIRC

P0715

0715

CVT-93

ISC SYSTEM

P0506

0506

EC-473

ISC SYSTEM

P0507

0507

EC-475

KNOCK SEN/CIRC-B1

P0327

0327

EC-359

KNOCK SEN/CIRC-B1

P0328

0328

EC-359

L/PRESS SOL/CIRC

P0745

0745

CVT-116

LU-SLCT SOL/CIRC

P1740

1740

CVT-166

MAF SEN/CIRCUIT

P0101

0101

EC-187

Items

 (CONSULT-II screen terms)

DTC*

1

Reference page

CONSULT-II

GST*

2

ECM*

3

EC-14

INDEX FOR DTC

Revision: 2006 August

2006 Murano

*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: The troubleshooting for this DTC needs CONSULT-II.
*5: When the fail-safe operations for both self-diagnoses occur at the same time, the MIL illuminates.

MAF SEN/CIRCUIT

P0102

0102

EC-196

MAF SEN/CIRCUIT

P0103

0103

EC-196

MULTI CYL MISFIRE

P0300

0300

EC-350

NATS MALFUNCTION

P1610 - P1615

1610 - 1615

BL-236

NO DTC IS DETECTED. 
FURTHER TESTING 
MAY BE REQUIRED.

P0000

0000

—

P-N POS SW/CIRCUIT

P0850

0850

EC-494

PNP SW/CIRC

P0705

0705

CVT-81

PRS CNT SOL/A FCTN

P0746

0746

CVT-121

PRS CNT SOL/B FCTN

P0776

0776

CVT-124

PRS CNT SOL/B CIRC

P0778

0778

CVT-127

PURG VOLUME CONT/V

P0443

0443

EC-401

PURG VOLUME CONT/V

P0444

0444

EC-409

PURG VOLUME CONT/V

P0445

0445

EC-409

PW ST P SEN/CIRC

P0550

0550

EC-477

SENSOR POWER/CIRC

P0643

0643

EC-489

STEP MOTR CIRC

P1777

1777

CVT-172

STEP MOTR FNC

P1778

1778

CVT-176

TCC SOLENOID/CIRC

P0740

0740

CVT-108

TCS/CIRC

P1212

1212

EC-501

TCS C/U FUNCTN

P1211

1211

EC-500

THERMSTAT FNCTN

P0128

0128

EC-227

TP SENSOR

P2135

2135

EC-584

TP SEN 1/CIRC

P0222

0222

EC-343

TP SEN 1/CIRC

P0223

0223

EC-343

TP SEN 2/CIRC

P0122

0122

EC-214

TP SEN 2/CIRC

P0123

0123

EC-214

TR PRS SENS/A CIRC

P0840

0840

CVT-137

TR PRS SENS/B CIRC

P0845

0845

CVT-145

TW CATALYST SYS-B1

P0420

0420

EC-381

TW CATALYST SYS-B2

P0430

0430

EC-381

V/SP SEN (A/T OUT)

P1720

1720

EC-540

VEH SPD SEN/CIR AT*

5

P0720

0720

CVT-98

VEH SPEED SEN/CIRC*

5

P0500

0500

EC-471

VENT CONTROL VALVE

P0447

0447

EC-416

VENT CONTROL VALVE

P0448

0448

EC-423

VIAS S/V CIRC

P1800

1800

EC-542

Items

 (CONSULT-II screen terms)

DTC*

1

Reference page

CONSULT-II

GST*

2

ECM*

3

PRECAUTIONS

EC-15

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Revision: 2006 August

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PRECAUTIONS

PFP:00001

Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT 
BELT PRE-TENSIONER”

NBS002YC

The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.

WARNING:

●

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

●

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

●

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.

On Board Diagnostic (OBD) System of Engine and CVT

NBS002YD

The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.

CAUTION:

●

Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves,
etc. will cause the MIL to light up.

●

Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)

●

Certain systems and components, especially those related to OBD, may use a new style slide-
locking type harness connector. For description and how to disconnect, refer to 

PG-62, "HAR-

NESS CONNECTOR"

 .

●

Be sure to route and secure the harnesses properly after work. The interference of the harness
with a bracket, etc. may cause the MIL to light up due to the short circuit.

●

Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.

●

Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.

Precaution

NBS002YE

●

Always use a 12 volt battery as power source.

●

Do not attempt to disconnect battery cables while engine is
running.

●

Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect battery
ground cable. Failure to do so may damage the ECM
because battery voltage is applied to ECM even if ignition
switch is turned OFF.

●

Before removing parts, turn ignition switch OFF and then
disconnect battery ground cable.

SEF289H

EC-16

PRECAUTIONS

Revision: 2006 August

2006 Murano

●

Do not disassemble ECM.

●

If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.

●

If the battery is disconnected, the following emission-
related diagnostic information will be lost within 24 hours.

–

Diagnostic trouble codes

–

1st trip diagnostic trouble codes

–

Freeze frame data

–

1st trip freeze frame data

–

System readiness test (SRT) codes

–

Test values

●

When connecting ECM harness connector, fasten it
securely with levers as far as they will go as shown in the
figure.

●

When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.

●

Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.

●

Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.

●

Keep engine control system parts and harness dry.

●

Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to 

EC-102, "ECM Terminals and Reference Value"

.

●

Handle mass air flow sensor carefully to avoid damage.

●

Do not disassemble mass air flow sensor.

●

Do not clean mass air flow sensor with any type of deter-
gent.

●

Do not disassemble electric throttle control actuator.

●

Even a slight leak in the air intake system can cause seri-
ous incidents.

●

Do not shock or jar the camshaft position sensor (PHASE), crankshaft position sensor (POS).

PBIB1164E

PBIB1512E

PBIB0090E

MEF040D

PRECAUTIONS

EC-17

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Revision: 2006 August

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●

After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.

●

When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.

●

Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.

●

B1 indicates the bank 1, B2 indicates the bank 2 as shown
in the figure.

SEF217U

SEF348N

SEC893C

EC-18

PRECAUTIONS

Revision: 2006 August

2006 Murano

●

Do not operate fuel pump when there is no fuel in lines.

●

Tighten fuel hose clamps to the specified torque.

●

Do not depress accelerator pedal when starting.

●

Immediately after starting, do not rev up engine unneces-
sarily.

●

Do not rev up engine just prior to shutdown.

●

When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.

–

Keep the antenna as far as possible from the electronic
control units.

–

Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.

–

Adjust the antenna and feeder line so that the standing-
wave radio can be kept smaller.

–

Be sure to ground the radio to vehicle body.

PBIB1356E

SEF709Y

SEF708Y

PREPARATION

EC-19

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Revision: 2006 August

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PREPARATION

PFP:00002

Special Service Tools

NBS002YG

The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.

Tool number
(Kent-Moore No.)
Tool name

Description

EG17650301
(J-33984-A)
Radiator cap tester 
adapter

Adapting radiator cap tester to radiator cap and 
radiator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)

KV10117100
(J-36471-A)
Heated oxygen 
sensor wrench

Loosening or tightening heated oxygen sensor with 
22 mm (0.87 in) hexagon nut

KV10114400
(J-38365)
Heated oxygen 
sensor wrench

Loosening or tightening heated oxygen sensor
a: 22 mm (0.87 in)

(J-44321)
Fuel pressure gauge 
kit

Checking fuel pressure

KV109E0010
(J-46209)
Break-out box

Measuring the ECM signals with a circuit tester

KV109E0080
(J-45819)
Y-cable adapter

Measuring the ECM signals with a circuit tester

S-NT564

S-NT379

S-NT636

LEC642

S-NT825

S-NT826

EC-20

PREPARATION

Revision: 2006 August

2006 Murano

Commercial Service Tools

NBS002YH

Tool name
(Kent-Moore No.)

Description

Leak detector 
i.e.: (J-41416)

Locating the EVAP leak

EVAP service port 
adapter
i.e.: (J-41413-OBD)

Applying positive pressure through EVAP service 
port

Fuel filler cap adapter
i.e.: (MLR-8382)

Checking fuel tank vacuum relief valve opening 
pressure

Socket wrench

Removing and installing engine coolant 
temperature sensor

Oxygen sensor thread 
cleaner
i.e.: (J-43897-18)
(J-43897-12)

Reconditioning the exhaust system threads 
before installing a new oxygen sensor. Use with 
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for 
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for 
Titania Oxygen Sensor

Anti-seize lubricant 

i.e.: (Permatex

TM

   

133AR or equivalent 
meeting MIL 
specification MIL-A-
907)

Lubricating oxygen sensor thread cleaning tool 
when reconditioning exhaust system threads.

S-NT703

S-NT704

S-NT815

S-NT705

AEM488

S-NT779

ENGINE CONTROL SYSTEM

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ENGINE CONTROL SYSTEM

PFP:23710

System Diagram

NBS002YI

PBIB2307E

EC-22

ENGINE CONTROL SYSTEM

Revision: 2006 August

2006 Murano

Multiport Fuel Injection (MFI) System

NBS002YJ

INPUT/OUTPUT SIGNAL CHART

*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This signals is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION

The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.

VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION

In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.

<Fuel increase>

●

During warm-up

●

When starting the engine

●

During acceleration

●

Hot-engine operation

●

When shift lever is changed from N to D

●

High-load, high-speed operation

<Fuel decrease>

●

During deceleration

●

During high engine speed operation

Sensor

Input Signal to ECM

ECM function

Actuator

Crankshaft position sensor (POS)

Engine speed*

3

Piston position

Fuel injection 
& mixture ratio 
control

Fuel injector

Camshaft position sensor (PHASE)

Mass air flow sensor

Amount of intake air

Engine coolant temperature sensor

Engine coolant temperature

Air fuel ratio (A/F) sensor 1

Density of oxygen in exhaust gas

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Park/neutral position (PNP) switch

Gear position

Knock sensor

Engine knocking condition

Battery

Battery voltage*

3

Power steering pressure sensor

Power steering operation

Heated oxygen sensor 2*

1

Density of oxygen in exhaust gas

Air conditioner switch

Air conditioner operation*

2

Wheel sensor

Vehicle speed*

2

ENGINE CONTROL SYSTEM

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MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)

The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses air
fuel ratio (A/F) sensor 1 in the exhaust manifold to monitor whether the engine operation is rich or lean. The
ECM adjusts the injection pulse width according to the sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to 

EC-229, "DTC P0130, P0150 A/F SENSOR 1"

 . This maintains the mixture

ratio within the range of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst (manifold). Even if the switching
characteristics of air fuel ratio (A/F) sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.

Open Loop Control

The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.

●

Deceleration and acceleration

●

High-load, high-speed operation

●

Malfunction of A/F sensor 1 or its circuit

●

Insufficient activation of A/F sensor 1 at low engine coolant temperature

●

High engine coolant temperature

●

During warm-up

●

After shifting from N to D

●

When starting the engine

MIXTURE RATIO SELF-LEARNING CONTROL

The mixture ratio feedback control system monitors the mixture ratio signal transmitted from A/F sensor 1.
This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to the theoret-
ical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as originally
designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic changes dur-
ing operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from A/F sensor 1 indicates whether the mixture ratio is RICH or LEAN compared to the the-
oretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an increase in
fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.

PBIB3020E

EC-24

ENGINE CONTROL SYSTEM

Revision: 2006 August

2006 Murano

FUEL INJECTION TIMING

Two types of systems are used.

Sequential Multiport Fuel Injection System

Fuel is injected into each cylinder during each engine cycle according to the firing order. This system is used
when the engine is running.

Simultaneous Multiport Fuel Injection System

Fuel is injected simultaneously into all six cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The six fuel injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.

FUEL SHUT-OFF

Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.

Electronic Ignition (EI) System

NBS002YK

INPUT/OUTPUT SIGNAL CHART

*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION

Firing order: 1 - 2 - 3 - 4 - 5 - 6
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-
ing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in
the ECM.

●

At starting

●

During warm-up

●

At idle

●

At low battery voltage

SEF179U

Sensor

Input Signal to ECM

ECM function

Actuator

Crankshaft position sensor (POS)

Engine speed*

2

Piston position

Ignition timing 
control

Power transistor

Camshaft position sensor (PHASE)

Mass air flow sensor

Amount of intake air

Engine coolant temperature sensor

Engine coolant temperature

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Knock sensor

Engine knocking

Park/neutral position (PNP) switch

Gear position

Battery

Battery voltage*

2

Wheel sensor

Vehicle speed*

1

ENGINE CONTROL SYSTEM

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●

During acceleration

The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.

Fuel Cut Control (at No Load and High Engine Speed)

NBS002YL

INPUT/OUTPUT SIGNAL CHART

*: This signal is sent to the ECM through CAN communication line.

SYSTEM DESCRIPTION

If the engine speed is above 1,800 rpm under no load (for example, the shift position is neutral and engine
speed over is 1,800 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will be cancelled.

NOTE:
This function is different from deceleration control listed under “Multiport Fuel Injection (MFI) System”, 

EC-22

 .

Sensor

Input Signal to ECM

ECM function

Actuator

Park/neutral position (PNP) switch

Neutral position

Fuel cut con-
trol

Fuel injector

Accelerator pedal position sensor

Accelerator pedal position

Engine coolant temperature sensor

Engine coolant temperature

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed

Wheel sensor

Vehicle speed*

EC-26

AIR CONDITIONING CUT CONTROL

Revision: 2006 August

2006 Murano

AIR CONDITIONING CUT CONTROL

PFP:23710

Input/Output Signal Chart

NBS002YM

*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

System Description

NBS002YN

This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.

●

When the accelerator pedal is fully depressed.

●

When cranking the engine.

●

At high engine speeds.

●

When the engine coolant temperature becomes excessively high.

●

When operating power steering during low engine speed or low vehicle speed.

●

When engine speed is excessively low.

●

When refrigerant pressure is excessively low or high.

Sensor

Input Signal to ECM

ECM function

Actuator

Air conditioner switch

Air conditioner ON signal*

1

Air conditioner 
cut control

Air conditioner relay

Accelerator pedal position sensor

Accelerator pedal position

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed*

2

Engine coolant temperature sensor

Engine coolant temperature

Battery

Battery voltage*

2

Refrigerant pressure sensor

Refrigerant pressure

Power steering pressure sensor

Power steering operation

Wheel sensor

Vehicle speed*

1