Infiniti M35/M45 Y50. Manual — part 529

DTC P1805 BRAKE SWITCH

EC-589

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

DTC P1805 BRAKE SWITCH

PFP:25320

Component Description

NBS0055Q

Brake switch signal is applied to the ECM through the stop lamp
switch (1) when the brake pedal is depressed. This signal is used
mainly to decrease the engine speed when the vehicle is driving.

●

ICC brake switch (models with ICC) (2)

●

ASCD brake switch (models with ASCD) (2)

CONSULT-II Reference Value in Data Monitor Mode

NBS0055R

Specification data are reference values.

On Board Diagnosis Logic

NBS0055S

The MIL will not light up for this diagnosis.

FAIL-SAFE MODE

When the malfunction is detected, ECM enters fail-safe mode.

PBIB2705E

MONITOR ITEM

CONDITION

SPECIFICATION

BRAKE SW

●

Ignition switch: ON

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1805
1805

Brake switch

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

Engine operating condition in fail-safe mode

ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.
Therefore, acceleration will be poor.

Vehicle condition

Driving condition

When engine is idling

Normal

When accelerating

Poor acceleration

EC-590

[VQ35DE]

DTC P1805 BRAKE SWITCH

DTC Confirmation Procedure

NBS0055T

WITH CONSULT-II

1.

Turn ignition switch ON.

2.

Fully depress the brake pedal for at least 5 seconds.

3.

Erase the DTC with CONSULT-II.

4.

Select “DATA MONITOR” mode with CONSULT-II.

5.

If 1st trip DTC is detected, go to

EC-592, "Diagnostic Procedure"

.

WITH GST

Follow the procedure “WITH CONSULT-II” above.

SEF058Y

DTC P1805 BRAKE SWITCH

EC-591

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

Wiring Diagram

NBS0055U

TBWT0986E

EC-592

[VQ35DE]

DTC P1805 BRAKE SWITCH

Specification data are reference values and are measured between each terminal and ground.

CAUTION:

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

Diagnostic Procedure

NBS0055V

ICC MODELS

1.

CHECK DTC WITH ICC SENSOR INTEGRATED UNIT

Refer to

ACS-40, "TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace.

2.

CHECK STOP LAMP SWITCH CIRCUIT

1.

Turn ignition switch OFF.

2.

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

OK or NG

OK

>> GO TO 5.

NG

>> GO TO 3.

TER-

MINAL

NO.

WIRE

COLOR

ITEM

CONDITION

DATA (DC Voltage)

101

V/R

Stop lamp switch

[Ignition switch: OFF]

●

Brake pedal: Fully released

Approximately 0V

[Ignition switch: OFF]

●

Brake pedal: Slightly depressed

BATTERY VOLTAGE
(11 - 14V)

Brake pedal

Stop lamp

Fully released

Not illuminated

Slightly depressed

Illuminated