2008 INFINITI FX35 brake light

DTC P1572 ASCD BRAKE SWITCHEC-475
< SERVICE INFORMATION > [VQ35DE]
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TESTING CONDITION:
Steps 4 and 5 may be conducted with the drive wheels li
fted in the shop or by driving the vehicle. If a
road test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Start engine.
2. Select “DATA MONITOR” mode with CONSULT-III.
3. Press MAIN switch and make sure that CRUISE indicator lights up.
4. Drive the vehicle for at least 5 consecutive seconds under the following condition.
5. Check 1st trip DTC.
If 1st trip DTC is detected, go to EC-477, "
Diagnosis Procedure".
If 1st trip DTC is not detected, go to the following step.
6. Drive the vehicle for at least 5 consecutive seconds under the following condition.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-477, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
Driving location Depress the brake pedal for more than
five seconds so as not to come off from
the above-mentioned vehicle speed.
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DTC P1572 ASCD BRAKE SWITCHEC-477
< SERVICE INFORMATION > [VQ35DE]
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Diagnosis ProcedureINFOID:0000000001326342
1.CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-III
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.
2.CHECK OVERALL FUNCTION-II
With CONSULT-III
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-III
Check voltage between ECM terminal 101 and ground under the following conditions.
TER-
MI-
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NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
101 P/L Stop lamp switch [Ignition switch: OFF]
 Brake pedal: Fully released
Approximately 0V
[Ignition switch: OFF]
 Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
108 SB ASCD brake switch [Ignition switch: ON]
 Brake pedal: Slightly depressed
Approximately 0V
[Ignition switch: ON]
 Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14V)
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
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EC-478
< SERVICE INFORMATION >[VQ35DE]
DTC P1572 ASCD BRAKE SWITCH
OK or NG
OK >> GO TO 13.
NG >> GO TO 8.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block (J/B) connector E201
 10A fuse
 Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
MBIB0060E
PBIB1605E
Voltage: Battery voltage
PBIB0857E
Continuity should exist.
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EC-480
< SERVICE INFORMATION >[VQ35DE]
DTC P1572 ASCD BRAKE SWITCH
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E211, M41
 Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK STOP LAMP SWITCH
Refer to EC-480, "
Component Inspection"
OK or NG
OK >> GO TO 13.
NG >> Replace stop lamp switch.
13.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
Component InspectionINFOID:0000000001326343
ASCD BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Check continuity between ASCD brake switch terminals 1 and 2
under the following conditions.
If NG, adjust ASCD brake switch installation, refer to BR-5
, 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.
If NG, adjust stop lamp switch installation, refer to BR-5
, and
perform step 3 again.
Condition Continuity
Brake pedal: Fully released Should exist
Brake pedal: Slightly depressed Should not exist
SEC023D
Condition Continuity
Brake pedal: Fully released Should not exist
Brake pedal: Slightly depressed Should exist
PBIB1185E
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EC-486
< SERVICE INFORMATION >[VQ35DE]
DTC P1805 BRAKE SWITCH
DTC P1805 BRAKE SWITCH
DescriptionINFOID:0000000001326356
Brake switch signal is applied to the ECM through t
he stop lamp switch when the brake pedal is depressed.
This signal is used mainly to decrease the engine speed when the vehicle is driving.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326357
Specification data are reference values.
On Board Diagn osis LogicINFOID:0000000001326358
The MIL will not light up for this self-diagnosis.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation ProcedureINFOID:0000000001326359
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-III.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-488, "
Diagnosis Procedure".
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 ex-
tremely long time while the vehicle is driving.  Harness or connectors
(Stop lamp switch circuit is open or short-
ed.)
 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
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EC-488
< SERVICE INFORMATION >[VQ35DE]
DTC P1805 BRAKE SWITCH
Diagnosis Procedure
INFOID:0000000001326361
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 SWIT CH POWER SUPPLY CIRCUIT
1. Disconnect stop lamp switch harness connector.
2. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 10A fuse
 Fuse block (J/B) connector E201
 Harness for open and short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
TER-MI-
NAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
101 P/L 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
PBIB1605E
Voltage: Battery voltage
PBIB1184E
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DTC P1805 BRAKE SWITCHEC-489
< SERVICE INFORMATION > [VQ35DE]
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1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect stop lamp switch harness connector.
4. Check harness continuity between ECM terminal 101 and stop
lamp switch terminal 2.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E211, M41
 Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK STOP LAMP SWITCH
Refer to EC-489, "
Component Inspection".
OK or NG
OK >> GO TO 7.
NG >> Replace stop lamp switch.
7.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
Component InspectionINFOID:0000000001326362
STOP LAMP SWITCH
1. Disconnect stop lamp switch harness connector.
2. Check continuity between stop lamp switch terminals 1 and 2
under the following conditions.
If NG, adjust stop lamp switch installation, refer to BR-5
, and
perform step 2 again. Continuity should exist.
PBIB1605E
PBIB1605E
Conditions Continuity
Brake pedal: Fully released Should not exist
Brake pedal: Slightly depressed Should exist
PBIB1185E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-542
< SERVICE INFORMATION >[VQ35DE]
ASCD BRAKE SWITCH
ASCD BRAKE SWITCH
Component DescriptionINFOID:0000000001326426
When the brake pedal is depressed, ASCD brake switch is turned
OFF and stop lamp switch is turned ON. ECM detects the state of
the brake pedal by this input of two kinds (ON/OFF signal).
Refer to
EC-37
for the ASCD function.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326427
Specification data are reference values.
PBIB1089E
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW 1
(ASCD brake switch)  Ignition switch: ON Brake pedal: Fully released ON
 Brake pedal: Slightly depressed OFF
BRAKE SW 2
(Stop lamp switch)  Ignition switch: ON Brake pedal: Fully released OFF
 Brake pedal: Slightly depressed ON
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C