Nissan Pathfinder. Instruction - part 521

EC-390

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1800 VIAS CONTROL SOLENOID VALVE 1

4. Also check harness for short to ground and short to power.
Is the inspection result normal?

YES

>> GO TO 3.

NO

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

3.

CHECK VIAS CONTROL SOLENOID VALVE 1

Check VIAS control solenoid valve 1. Refer to 

EC-391, "Component Inspection"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-49, "Intermittent Incident"

.

NO

>> Replace VIAS control solenoid valve 1. Refer to 

EC-14, "ENGINE CONTROL SYSTEM : Compo-

nent Parts Location"

.

Component Inspection

INFOID:0000000009178313

1.

CHECK VIAS CONTROL SOLENOID VALVE 1

With CONSULT

1. Turn ignition switch OFF.

2. Reconnect all harness connectors disconnected.

3. Disconnect vacuum hoses connected to VIAS control solenoid valve 1.

4. Turn ignition switch ON.

5. Select “VIAS S/V-1” in “ACTIVE TEST” mode with CONSULT.

6. Check air passage continuity and operation delay time under the

following conditions.

Without CONSULT

1. Turn ignition switch OFF.

2. Disconnect VIAS control solenoid valve 1 harness connector.

3. Disconnect vacuum hoses connected to VIAS volume control solenoid valve 1.

4. Check air passage continuity and operation delay time under the

following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace VIAS control solenoid valve 1. Refer to 

EC-14, "ENGINE CONTROL SYSTEM : Compo-

nent Parts Location"

.

VIAS control solenoid valve 1

ECM

Continuity

Connector

Terminal

Connector

Terminal

F66

2

F51

39

Existed

Condition

(VIAS S/V-1)

Air passage continuity 

between  

and 

Air passage continuity 

between  

and 

ON

Existed

Not existed

OFF

Not existed

Existed

JMBIA0180ZZ

Condition

Air passage continuity 

between  

and 

Air passage continuity 

between  

and 

12 V direct current supply 
between terminals 1 and 2

Existed

Not existed

No supply

Not existed

Existed

PBIB2532E

P1801 VIAS CONTROL SOLENOID VALVE 2

EC-391

< DTC/CIRCUIT DIAGNOSIS >

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P1801 VIAS CONTROL SOLENOID VALVE 2

DTC Logic

INFOID:0000000009178314

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

CONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:

Before performing the following procedure, confirm battery voltage is more than 11 V at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for at least 5 seconds.

2. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Proceed to 

EC-392, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009178315

1.

CHECK VIAS CONTROL SOLENOID VALVE 2 POWER SUPPLY

1. Turn ignition switch OFF.

2. Disconnect VIAS control solenoid valve 2 harness connector.

3. Turn ignition switch ON.

4. Check the voltage between VIAS control solenoid valve 2 harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 2.

NO

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

2.

CHECK VIAS CONTROL SOLENOID VALVE 2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between VIAS control solenoid valve 2 harness connector and ECM harness con-

nector.

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P1801

VIAS S/V CIRC-B2
(VIAS solenoid valve circuit 
bank 2)

An excessively low or high voltage signal 
is sent to ECM through the VIAS control 
solenoid valve 2.

• Harness or connectors

(The solenoid valve 2 circuit is open or 
shorted.)

• VIAS control solenoid valve 2

VIAS control solenoid valve 2

Ground

Voltage

Connector

Terminal

F67

1

Ground

Battery voltage

EC-392

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1801 VIAS CONTROL SOLENOID VALVE 2

4. Also check harness for short to ground and short to power.
Is the inspection result normal?

YES

>> GO TO 3.

NO

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

3.

CHECK VIAS CONTROL SOLENOID VALVE 2

Check VIAS control solenoid valve 2. Refer to 

EC-393, "Component Inspection"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-49, "Intermittent Incident"

.

NO

>> Replace VIAS control solenoid valve 2. Refer to 

EC-14, "ENGINE CONTROL SYSTEM : Compo-

nent Parts Location"

.

Component Inspection

INFOID:0000000009178316

1.

CHECK VIAS CONTROL SOLENOID VALVE 2

With CONSULT

1. Turn ignition switch OFF.

2. Reconnect all harness connectors disconnected.

3. Disconnect vacuum hoses connected to VIAS control solenoid valve 2.

4. Turn ignition switch ON.

5. Select “VIAS S/V-2” in “ACTIVE TEST” mode with CONSULT.

6. Check air passage continuity and operation delay time under the

following conditions.

Without CONSULT

1. Turn ignition switch OFF.

2. Disconnect VIAS control solenoid valve 2 harness connector.

3. Disconnect vacuum hoses connected to VIAS volume control solenoid valve 2.

4. Check air passage continuity and operation delay time under the

following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace VIAS control solenoid valve 2. Refer to 

EC-14, "ENGINE CONTROL SYSTEM : Compo-

nent Parts Location"

.

VIAS control solenoid valve 2

ECM

Continuity

Connector

Terminal

Connector

Terminal

F67

2

F51

40

Existed

Condition

(VIAS S/V-2)

Air passage continuity 

between  

and 

Air passage continuity 

between  

and 

ON

Existed

Not existed

OFF

Not existed

Existed

JMBIA0180ZZ

Condition

Air passage continuity 

between  

and 

Air passage continuity 

between  

and 

12 V direct current supply 
between terminals 1 and 2

Existed

Not existed

No supply

Not existed

Existed

PBIB2532E

P1805 BRAKE SWITCH

EC-393

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

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P1805 BRAKE SWITCH

Description

INFOID:0000000009178317

Brake switch signal is applied to the ECM via the stop lamp switch when the brake pedal is depressed. This

signal is used mainly to decrease the engine speed when the vehicle is driven.

DTC Logic

INFOID:0000000009178318

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch ON.

2. Fully depress the brake pedal for at least 5 seconds.

3. Erase the DTC with CONSULT.

4. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-394, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009178319

1.

CHECK STOP LAMP SWITCH CIRCUIT

1. Turn ignition switch OFF.

2. Check the stop lamp when depressing and releasing the brake pedal.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-49, "Intermittent Incident"

.

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH POWER SUPPLY

1. Disconnect stop lamp switch harness connector.

2. Check the voltage between stop lamp switch harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Perform the trouble diagnosis for power supply circuit.

3.

CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT

1. Disconnect ECM harness connector.

2. Check the continuity between stop lamp switch harness connector and ECM harness connector.

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P1805

BRAKE SW/CIRCUIT
(Stop lamp switch circuit)

A brake switch signal is not sent to ECM 
for extremely long time while the vehicle is 
driving.

• Harness or connectors

(Stop lamp switch circuit is open or shorted.)

• Stop lamp switch

Brake pedal

Stop lamp

Fully released

Not illuminated

Slightly depressed

Illuminated

Stop lamp switch

Ground

Voltage

Connector

Terminal

E38

1

Ground

Battery voltage