2006 INFINITI M35 brake light

EC-598
[VQ35DE]
DTC P1805 BRAKE SWITCH
Revision: 2006 January2006 M35/M45
DTC P1805 BRAKE SWITCHPFP:25320
Component DescriptionNBS0055Q
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 ModeNBS0055R
Specification data are reference values.
On Board Diagnosis LogicNBS0055S
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: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1805
1805Brake switchA 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

DTC P1805 BRAKE SWITCH
EC-601
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 January2006 M35/M45
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 ProcedureNBS0055V
ICC MODELS
1. CHECK DTC WITH ICC UNIT
Refer to ACS-39, "
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
COLORITEM CONDITION DATA (DC Voltage)
101 V/R Stop lamp switch[Ignition switch: OFF]
Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
Brake pedal Stop lamp
Fully released Not illuminated
Slightly depressed Illuminated

EC-604
[VQ35DE]
DTC P1805 BRAKE SWITCH
Revision: 2006 January2006 M35/M45
ASCD MODELS
1. 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 4.
NG >> GO TO 2.
2. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Disconnect stop lamp switch (1) harness connector.
–ASCD brake switch (2)
2. Check voltage between stop lamp switch terminal 1 and ground
with CONSULT -II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.
Fuse block (J/B) connector E101
10A fuse
Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
Brake pedal Stop lamp
Fully released Not illuminated
Slightly depressed Illuminated
PBIB2705E
Voltage: Battery voltage
PBIA9488J

EC-606
[VQ35DE]
DTC P1805 BRAKE SWITCH
Revision: 2006 January2006 M35/M45
Component InspectionNBS0055W
STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check harness continuity between stop lamp switch terminals 1
and 2 under the following conditions.
4. If NG, adjust stop lamp switch installation, refer to BR-6,
"BRAKE PEDAL" , and perform step 3 again.
ICC BRAKE HOLD RELAY
1. Check continuity between ICC brake hold relay terminals 3 and
5 under the following conditions.
2. If NG, replace ICC brake hold relay.
Condition Continuity
When brake pedal: Fully released. Should not exist.
When brake pedal: Slightly depressed. Should exist.
PBIA9489J
Condition Continuity
12V direct current supply between terminals
1 and 2Should not exist
No current supply Should exist
PBIB0098E

ICC BRAKE SWITCH
EC-699
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 January2006 M35/M45
ICC BRAKE SWITCHPFP:25320
Component DescriptionNBS0058C
When the brake pedal is depressed, ICC brake switch (2) is turned
OFF and stop lamp switch (1) is turned ON. ECM detects the state of
the brake pedal by this input of two kinds (ON/OFF signal).
Refer to ACS-6, "
DESCRIPTION" for the ICC function.
CONSULT-II Reference Value in Data Monitor ModeNBS0058D
Specification data are reference values.
PBIB2705E
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW1
(ICC brake switch)
Ignition switch: ONBrake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
BRAKE SW2
(Stop lamp switch)
Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON

ICC BRAKE SWITCH
EC-701
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2006 January2006 M35/M45
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 ProcedureNBS0058F
1. CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CON-
SULT-II.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
101 V/R Stop lamp switch[Ignition switch: OFF]
Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
108 BR ICC brake switch[Ignition switch: ON]
Brake pedal: Slightly depressedApproximately 0V
[Ignition switch: ON]
Brake pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V)
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
SEC011D
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E

EC-702
[VQ35DE]
ICC BRAKE SWITCH
Revision: 2006 January2006 M35/M45
2. CHECK OVERALL FUNCTION-II
With CONSULT-II
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-II
Check voltage between ECM terminal 101 and ground under the fol-
lowing conditions.
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
3. CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch (2) harness connector.
–Stop lamp switch (1)
3. Turn ignition switch ON.
4. Check voltage between ICC brake switch terminal 1 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
SEC013D
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
PBIB2705E
Voltage: Battery voltage
PBIB0857E

EC-706
[VQ35DE]
ICC BRAKE SWITCH
Revision: 2006 January2006 M35/M45
2. Disconnect ICC brake switch harness connector.
3. Check continuity between ICC brake switch terminals 1 and 2
under the following conditions.
4. If NG, adjust ICC brake switch installation, refer to BR-6,
"BRAKE PEDAL" , and perform step 3 again.
STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check continuity between stop lamp switch terminals 1 and 2
under the following conditions.
4. If NG, adjust stop lamp switch installation, refer to BR-6,
"BRAKE PEDAL" , and perform step 3 again.
ICC BRAKE HOLD RELAY
1. Check continuity between ICC brake hold relay terminals 3 and
5 under the following conditions.
2. If NG, replace ICC brake hold relay.
Condition Continuity
Brake pedal: Fully released. Should exist.
Brake pedal: Slightly depressed. Should not exist.
PBIB1536E
Condition Continuity
Brake pedal: Fully released. Should not exist.
Brake pedal: Slightly depressed. Should exist.
PBIA9489J
Condition Continuity
12V direct current supply between terminals
1 and 2Should not exist
No current supply Should exist
PBIB0098E