Nissan Xterra. Manual - part 333

EC-458

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

ASCD INDICATOR

ASCD INDICATOR

Component Description

INFOID:0000000009484212

ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and

SET, and is integrated in combination meter.

CRUISE indicator illuminates when MAIN switch on ASCD steering switch is turned ON to indicated that

ASCD system is ready for operation.

SET indicator illuminates when the following conditions are met. 

• CRUISE indicator is illuminated.

• SET/COAST switch on ASCD steering switch is turned ON while vehicle speed is within the range of the

ASCD setting.

SET indicator remains lit during ASCD control.

Refer to 

EC-28, "System Description"

 for the ASCD function.

Diagnosis Procedure

INFOID:0000000009484213

1.

CHECK OVERALL FUNCTION

Check ASCD indicator under the following conditions.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 2.

2.

CHECK DTC

Check that DTC UXXXX is not displayed.
OK or NG

OK

>> GO TO 3.

NG

>> Perform trouble diagnoses for DTC UXXXX. 

3.

CHECK COMBINATION METER FUNCTION

Refer to 

MWI-4, "Work Flow"

.

OK or NG

OK

>> GO TO 4.

NG

>> Go to 

MWI-5, "METER SYSTEM : System Diagram"

.

4.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

>> INSPECTION END

ASCD INDICATOR

CONDITION

SPECIFICATION

CRUISE LAMP

• Ignition switch: ON

MAIN switch: pressed at the 1st time 
→ at the 2nd time

ON 

→ OFF

SET LAMP

• MAIN  switch:  ON
• When vehicle speed is be-

tween 40 km/h (25 MPH) and 
144 km/h (89 MPH)

ASCD: Operating

ON

ASCD: Not operating

OFF

COOLING FAN

EC-459

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

COOLING FAN

Description

INFOID:0000000009484214

COMPONENT DESCRIPTION

Cooling Fan Motor

The cooling fan operates at each speed when the current flows in the cooling fan motor as follows.

Diagnosis Procedure

INFOID:0000000009484215

1.

CHECK IPDM E/R GROUND CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect IPDM E/R harness connectors E122, E124.

3. Check harness continuity between IPDM E/R terminals 38, 59 and ground.

Refer to Wiring Diagram.

4. Also check harness for short to power.
OK or NG

OK

>> GO TO 2.

NG

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

2.

CHECK COOLING FAN MOTOR CIRCUIT FOR OPEN AND SHORT

1. Disconnect cooling fan motor harness connector.

2. Check harness continuity between the following;

cooling fan motor terminal 1 and IPDM E/R terminal 20,

cooling fan motor terminal 2 and IPDM E/R terminal 24.

Refer to Wiring Diagram.

3. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 3.

NG

>> Repair open circuit or short to ground or short to power

in harness or connectors.

3.

CHECK COOLING FAN MOTER GROUND CIRCUIT FOR OPEN OR SHORT

1. Check harness continuity between the following;

cooling fan motor terminal 3 and ground,

cooling fan motor terminal 4 and ground.

Refer to Wiring Diagram.

2. Also check harness for short to power.
OK or NG

OK

>> GO TO 4.

NG

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

Cooling fan speed

Cooling fan motor terminals

(+)

(

−)

Low (LOW)

1

3 and 4

2

3 and 4

High (HI)

1 and 2

3 and 4

Continuity should exist.

Continuity should exist.

BBIA0555E

Continuity should exist.

EC-460

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

COOLING FAN

4.

CHECK COOLING FAN MOTOR

Refer to 

EC-460, "Component Inspection"

.

OK or NG

OK

>> GO TO 5.

NG

>> Replace cooling fan motor. Refer to 

CO-18, "Exploded View"

.

5.

CHECK INTERMITTENT INCIDENT

Perform 

GI-40, "Intermittent Incident"

.

OK or NG

OK

>> INSPETION END

NG

>> Repair or replace harness or connector. 

Component Inspection

INFOID:0000000009484216

COOLING FAN MOTOR

1. Disconnect cooling fan motor harness connectors.
2. Supply cooling fan motor terminals with battery voltage and check operation.

Cooling fan motor should operate.

If NG, replace cooling fan motor.

Cooling fan speed

Cooling fan motor terminals

(+)

(

−)

Low

1

3 and 4

2

3 and 4

High

1 and 2

3 and 4

ELECTRICAL LOAD SIGNAL

EC-461

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

ELECTRICAL LOAD SIGNAL

Description

INFOID:0000000009484217

The electrical load signal (Headlamp switch signal, etc.) is transferred through the CAN communication line

from BCM to ECM via IPDM E/R.

Diagnosis Procedure

INFOID:0000000009484218

1.

CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I

1. Turn ignition switch ON.

2. Connect CONSULT and select “DATA MONITOR” mode.

3. Select “LOAD SIGNAL” and check indication under the following conditions.

OK or NG

OK

>> GO TO 2.

NG

>> GO TO 4.

2.

CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II

Check “LOAD SIGNAL” indication under the following conditions.

OK or NG

OK

>> GO TO 3.

NG

>> GO TO 5.

3.

CHECK HEATER FAN SIGNAL CIRCUIT OVERALL FUNCTION

Select “HEATER FAN SW” and check indication under the following conditions.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 6.

4.

CHECK REAR WINDOW DEFOGGER SYSTEM

Refer to 

DEF-3, "Repair Work Flow"

.

>> INSPECTION END

5.

CHECK HEADLAMP SYSTEM

Refer to 

EXL-4, "Work Flow"

.

>> INSPECTION END

6.

CHECK HEATER FAN CONTROL SYSTEM

Refer to 

HAC-52, "Symptom Matrix Chart"

.

Condition

Indication

Rear window defogger switch: ON

ON

Rear window defogger switch: OFF

OFF

Condition

Indication

Lighting switch: ON at 2nd position

ON

Lighting switch: OFF

OFF

Condition

Indication

Heater fan control switch: ON

ON

Heater fan control switch: OFF

OFF