Infiniti QX56 (Z62). Manual - part 619

EC-454

< DTC/CIRCUIT DIAGNOSIS >

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P1608 VVEL SENSOR POWER SUPPLY

4.

Also check harness for short to ground and power.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• Harness for open or short between VVEL control shaft position sensor and VVEL control module
• Loose or poor connection for each connector and harness

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

4.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> Replace VVEL control module. Refer to 

EC-536, "Removal and Installation"

.

NO

>> Repair or replace.

5.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace.

6.

REPLACE VVEL LADDER ASSEMBLY

Replace VVEL ladder assembly. Refer to 

EM-75, "Removal and Installation"

.

>> NSPECTION END

VVEL control shaft position sensor

VVEL control module

Continuity

Bank

Connector

Terminal

Connector

Terminal

1

F72

3

F56

7

Existed

6

20

2

F70

3

9

6

22

P1805 BRAKE SWITCH

EC-455

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

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P1805 BRAKE SWITCH

DTC Logic

INFOID:0000000006217957

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.

4.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-455, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006217958

1.

CHECK STOP LAMP SWITCH CIRCUIT

1.

Turn ignition switch OFF.

2.

Check for stop lamp illumination under the following conditions.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

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 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• 10 A fuse (No. 7)
• Harness for open or short between stop lamp switch and battery
• Loose or poor connection for each connector and harness

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

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P1805

BRAKE SW/CIRCUIT
(Brake switch)

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

• Harness or connectors

(Stop lamp switch circuit is open or shorted.)

• Stop lamp switch

Condition

Stop lamp

Brake pedal

Fully released

Not illuminated

Slightly depressed

Illuminated

Stop lamp switch

Ground

Voltage

Connector

Terminal

E115

1

Ground

Battery voltage

EC-456

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

P1805 BRAKE SWITCH

4.

CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect stop lamp switch harness connector.

2.

Disconnect ECM harness connector.

3.

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

4.

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

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.
• Harness for open or short between ECM and stop lamp switch
• Loose or poor connection for each connector and harness

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

6.

CHECK STOP LAMP SWITCH 

Refer to 

EC-456, "Component Inspection (Stop Lamp Switch)"

.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace stop lamp switch. Refer to 

BR-20, "Removal and Installation"

.

7.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection (Stop Lamp Switch)

INFOID:0000000006217959

1.

CHECK STOP LAMP SWITCH-I

1.

Turn ignition switch OFF.

2.

Disconnect stop lamp switch harness connector.

3.

Check the continuity between stop lamp switch terminals under the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH-II

1.

Adjust stop lamp switch installation. Refer to 

BR-21, "Inspection and Adjustment"

.

2.

Check the continuity between stop lamp switch terminals under the following conditions.

Is the inspection result normal?

Stop lamp switch

ECM

Continuity

Connector

Terminal

Connector

Terminal

E115

2

E80

158

Existed

Terminals

Condition

Continuity

1 and 2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

Terminals

Condition

Continuity

1 and 2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

P1805 BRAKE SWITCH

EC-457

< DTC/CIRCUIT DIAGNOSIS >

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YES

>> INSPECTION END

NO

>> Replace stop lamp switch. Refer to 

BR-20, "Removal and Installation"

.