Infiniti QX56 (Z62). Manual — part 636

EC-522

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

SNOW MODE SWITCH

SNOW MODE SWITCH

Description

INFOID:0000000006256403

The snow mode switch signal is sent to the combination meter from the snow mode switch. The combination
meter then sends the signal to the ECM via the CAN communication line.
The snow mode is used for driving or starting the vehicle on snowy roads or slippery areas. If the snow mode
is activated, the vehicle speed will not accelerate as quickly as normal to avoid vehicle slip. In other words,
ECM controls rapid engine torque change by controlling the electric throttle control actuator operating speed.

Component Function Check

INFOID:0000000006256404

1.

CHECK SNOW MODE SWITCH FUNCTION

1.

Turn ignition switch ON.

2.

Select “SNOW MODE SW” in “DATA MONITOR” mode with CONSULT-III.

3.

Check “SNOW MODE SW” indication under the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to

EC-522, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000006256405

1.

CHECK DTC WITH COMBINATION METER

Refer to

MWI-30, "CONSULT-III Function"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Go to

MWI-57, "Work flow"

.

2.

CHECK SNOW MODE SWITCH POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect snow mode switch harness connector.

3.

Turn ignition switch ON.

4.

Check the voltage between snow mode switch harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• Fuse block harness connector M3
• 10 A fuse (No. 13)
• Harness for open or short between snow mode switch and fuse.

>> Repair open circuit, short to ground or short to power in harness or connectors.

4.

CHECK SNOW MODE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

Monitor item

Condition

Indication

SNOW MODE SW

Snow mode switch

ON

ON

OFF

OFF

Snow mode switch

Ground

Voltage

Connector

Terminal

M54

12

Ground

Battery voltage

SNOW MODE SWITCH

EC-523

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

2.

Disconnect combination meter harness connector.

3.

Check the continuity between snow mode switch harness connector and combination meter harness con-
nector.

4.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair open circuit, short to ground or short to power in harness or connector.

5.

CHECK SNOW MODE SWITCH

Refer to

EC-523, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Replace snow mode switch. Refer to

IP-25, "Removal and Installation"

.

6.

CHECK INTERMITTENT INCIDENT

Refer to

GI-40, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000006256406

1.

CHECK SNOW MODE SWITCH

1.

Turn ignition switch OFF.

2.

Disconnect snow mode switch harness connector.

3.

Check the continuity between snow mode switch terminals under the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace snow mode switch. Refer to

IP-25, "Removal and Installation"

.

Snow mode switch

Combination meter

Continuity

Connector

Terminal

Connector

Terminal

M54

22

M34

33

Existed

Terminals

Condition

Continuity

12 and 22

Snow mode switch

ON

Existed

OFF

Not Existed

EC-524

< SYMPTOM DIAGNOSIS >

[VK56VD]

ENGINE CONTROL SYSTEM SYMPTOMS

SYMPTOM DIAGNOSIS

ENGINE CONTROL SYSTEM SYMPTOMS

Symptom Table

INFOID:0000000006218028

SYSTEM — BASIC ENGINE CONTROL SYSTEM

SYMPTOM

Reference
page

HARD/NO ST

AR

T

/REST

AR

T

(EXCP

.

H

A

)

ENGINE ST

ALL

HESIT

A

TION/SURGING/FLA

T

SPOT

SP

ARK KNOCK/DET

O

NA

TION

LACK

OF POWER/

POOR

ACC

E

LERA

TION

HIGH IDL

E/LOW

IDLE

ROUG

H IDLE/HUNTING

IDLI

NG VIBRA

TION

SLOW/NO RETURN T

O

IDLE

OVERHEA

T

S/W

A

TER TEMPERA

T

UR

E

HIGH

EXCESS

IVE F

U

E

L

CONSUMP

T

IO

N

EXCESS

IVE OIL CONSUMP

T

ION

BA

TTER

Y

DEAD (UNDER CHARGE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA

Fuel

Low pressure fuel pump circuit

1

1

2

3

2

2

2

3

2

EC-512

Low fuel pressure sensor circuit

4

4

EC-483

Fuel pressure regulator system

3

3

4

4

4

4

4

4

4

4

EC-198

Fuel injector circuit

1

1

2

3

2

2

2

2

EC-498

Evaporative emission system

3

3

4

4

4

4

4

4

4

4

EC-532

FRP sensor circuit

1

1

2

2

2

2

2

2

EC-276
EC-279

High pressure fuel pump circuit

4

3

EC-501

Air

Positive crankcase ventilation sys-
tem

3

3

4

4

4

4

4

4

4

4

1

EC-534

Incorrect idle speed adjustment

1

1

1

1

1

EC-139

Electric throttle control actuator

1

1

2

3

3

2

2

2

2

2

2

EC-460
EC-466

Ignition

Incorrect ignition timing adjustment

3

3

1

1

1

1

1

1

EC-139

Ignition circuit

1

1

2

2

2

2

2

2

EC-506

Main power supply and ground circuit

2

2

3

3

3

3

3

2

3

EC-168

ENGINE CONTROL SYSTEM SYMPTOMS

EC-525

< SYMPTOM DIAGNOSIS >

[VK56VD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Mass air flow sensor circuit

1

1

2

2

2

2

2

2

EC-201

Engine coolant temperature sensor circuit

3

3

3

EC-217

Air fuel ratio (A/F) sensor 1 circuit

EC-181
EC-228
EC-232
EC-235
EC-238

Throttle position sensor circuit

2

2

EC-219
EC-288
EC-406
EC-407
EC-475

Accelerator pedal position sensor circuit

3

2

1

EC-468
EC-471
EC-478

Knock sensor circuit

2

3

EC-297

Engine oil temperature sensor

4

2

3

EC-285

Crankshaft position sensor circuit

2

2

EC-299

Camshaft position sensor circuit

3

2

EC-303

Vehicle speed signal circuit

2

3

3

3

EC-356

Power steering pressure sensor circuit

2

3

3

EC-371

ECM

2

2

3

3

3

3

3

3

3

3

3

EC-376
EC-378
EC-380

Intake valve timing control solenoid valve cir-
cuit

3

2

1

3

2

2

3

3

EC-193

VVEL control module

3

4

4

3

EC-451
EC-452

VVEL actuator motor

3

4

4

3

EC-390

VVEL actuator motor relay

3

4

4

3

EC-393

VVEL control shaft position sensor

3

4

4

3

EC-387

PNP signal circuit

3

3

3

3

3

EC-383

Refrigerant pressure sensor circuit

2

3

3

4

EC-520

Electrical load signal circuit

3

EC-493

Air conditioner circuit

2

2

3

3

3

3

3

3

3

3

2

HAC-60

ABS actuator and electric unit (control unit)

4

BRC-60

SYMPTOM

Reference
page

HARD/NO S

T

A

R

T/RES

T

A

R

T (E

XCP

. HA)

E

N

GINE

ST

ALL

HES

IT

A

TION/SURGING/FLA

T

SPOT

S

P

ARK KNOC

K

/DET

O

NA

TI

ON

LACK OF

POWER/POOR ACCELERA

TION

HIG

H

IDL

E

/L

OW

ID

LE

ROUGH IDLE/HUNTING

ID

LING VI

BRA

T

ION

S

L

OW/NO RETU

RN

T

O ID

LE

OVERHEA

T

S

/W

A

TER TEMPERA

T

URE HIG

H

E

XCESSIVE

FUEL CON

S

UMP

T

ION

E

XCESSIVE

OIL

C

O

NSUMP

T

ION

B

A

TTER

Y

DEAD (UNDER CHARGE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA