2007 INFINITI QX56 brake sensor

AT-128
< SERVICE INFORMATION >
DTC P1731 A/T 1ST ENGINE BRAKING
DTC P1731 A/T 1ST ENGINE BRAKING
DescriptionINFOID:0000000003532348
Fail-safe function to prevent sudden decrease in speed by engine brake other than at "1" position.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532349
On Board Diagnosis LogicINFOID:0000000003532350
• This is not an OBD-II self-diagnostic item.
• Diagnostic trouble code “P1731 A/T 1ST E/BRAKING” with CONSULT-II is detected under the following con-
ditions.
- When TCM does not receive the proper voltage signal from the sensor.
- When TCM monitors each ATF pressure switch and solenoid monitor value, and detects as irregular when
engine brake of 1st gear acts other than at 1 position.
Possible CauseINFOID:0000000003532351
• Harness or connectors
(The sensor circuit is open or shorted.)
• Low coast brake solenoid valve
• ATF pressure switch 2
DTC Confirmation ProcedureINFOID:0000000003532352
NOTE:
If “DTC Confirmation Procedure” has been previously preformed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 2
consecutive seconds.
ENGINE SPEED: 1,200 rpm
Selector lever: “1” position
Gear position: 1st gear
5. If DTC is detected, go to AT-128, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000003532353
1.CHECK INPUT SIGNALS
With CONSULT-II
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
BCIA0031E

DTC P1731 A/T 1ST ENGINE BRAKING
AT-129
< SERVICE INFORMATION >
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1. Start the engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” for "A/
T" with CONSULT-II"
3. Drive vehicle in the “1” position (1st gear), and confirm the ON/
OFF actuation of “ATF PRES SW 2” and "ON OFF SOL".
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2.CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-158
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3.DETECT MALFUNCTIONING ITEM
Check the following items:
• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT-210, "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2".
NG >> Repair or replace damaged parts.
4.CHECK DTC
Perform “DTC Confirmation Procedure”.
• Refer to AT-128, "
DTC Confirmation Procedure".
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ON OFF
SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
ATF PRES
SW 2Low coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
PCIA0067E

AT-134
< SERVICE INFORMATION >
DTC P1757 FRONT BRAKE SOLENOID VALVE
DTC P1757 FRONT BRAKE SOLENOID VALVE
DescriptionINFOID:0000000003532366
Front brake solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehicle
speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be shifted to the
optimum position.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532367
On Board Diagnosis LogicINFOID:0000000003532368
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P1757 FR/B SOLENOID/CIRC” with CONSULT-II is detected under the following
conditions.
- When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
- When TCM detects as irregular by comparing target value with monitor value.
Possible CauseINFOID:0000000003532369
• Harness or connectors
(The solenoid circuit is open or shorted.)
• Front brake solenoid valve
DTC Confirmation ProcedureINFOID:0000000003532370
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 5
consecutive seconds.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 3rd ⇒ 4th Gear (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
5. If DTC is detected go to AT-134, "
Diagnosis Procedure".
WITH GST
Follow the procedure “With CONSULT-II”.
Diagnosis ProcedureINFOID:0000000003532371
1.CHECK INPUT SIGNAL
With CONSULT-II
Item name Condition Display value (Approx.)
FR/B SOLENOIDFront brake engaged. Refer to AT- 2 0
. 0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
.0 - 0.05 A
BCIA0031E

DTC P1757 FRONT BRAKE SOLENOID VALVE
AT-135
< SERVICE INFORMATION >
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1. Turn ignition switch “ON”.
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T”
with CONSULT-II.
3. Start engine.
4. Read out the value of “FR/B SOLENOID” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2.CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-158
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3.DETECT MALFUNCTIONING ITEM
Check the following items:
• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT-210, "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2".
NG >> Repair or replace damaged parts.
4.CHECK DTC
Perform “DTC Confirmation Procedure”.
• Refer to AT-134, "
DTC Confirmation Procedure".
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value (Ap-
prox.)
FR/B SOLE-
NOIDFront brake engaged. Refer to AT- 2 0
.0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
0 - 0.05 ASCIA4793E

AT-136
< SERVICE INFORMATION >
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION
DescriptionINFOID:0000000003532372
• Front brake solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehicle
speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be shifted to
the optimum position.
• This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunc-
tion such as control valve sticking, improper solenoid valve operation.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532373
On Board Diagnosis LogicINFOID:0000000003532374
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P1759 FR/B SOLENOID FNCT” with CONSULT-II is detected under the following
conditions.
- When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 1 is irregular during depressing accelerator pedal. (Other than during shift change)
- When TCM detects that relation between gear position and condition of ATF pressure switch 1 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseINFOID:0000000003532375
• Harness or connectors
(The solenoid and switch circuits are open or shorted.)
• Front brake solenoid valve
• ATF pressure switch 1
DTC Confirmation ProcedureINFOID:0000000003532376
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 3rd ⇒ 4th Gear (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3” again.
5. Check “SELF-DIAG RESULTS” mode for “A/T” with CONSULT-
II. If DTC (P1759) is detected, refer to AT-137, "
Diagnosis Pro-
cedure".
If DTC (P1757) is detected, go to AT-134, "
Diagnosis Procedure".
If DTC (P1841) is detected, go to AT-150, "
Diagnosis Procedure".
Item name Condition Display value (Approx.)
FR/B SOLENOIDFront brake engaged. Refer to AT- 2 0
. 0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
.0 - 0.05 A
ATF PRES SW 1Front brake engaged. Refer to AT- 2 0
.ON
Front brake disengaged. Refer to AT- 2 0
.OFF
BCIA0031E

DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION
AT-137
< SERVICE INFORMATION >
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Diagnosis ProcedureINFOID:0000000003532377
1.CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Drive vehicle in the “D” position (3rd ⇒ 4th gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 1” and electrical
current value of “FR/B SOLENOID”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2.CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-158
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3.DETECT MALFUNCTIONING ITEM
Check the following items:
• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT-210, "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2".
NG >> Repair or replace damaged parts.
4.CHECK DTC
Perform “DTC Confirmation Procedure”.
• Refer to AT-136, "
DTC Confirmation Procedure".
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value (Approx.)
FR/B SOLE-
NOIDFront brake engaged. Refer to AT- 2 0
. 0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
.0 - 0.05 A
ATF PRES
SW 1Front brake engaged. Refer to AT- 2 0
.ON
Front brake disengaged. Refer to AT- 2 0
.OFF
SCIA4796E

AT-146
< SERVICE INFORMATION >
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
DescriptionINFOID:0000000003532402
Low coast brake solenoid valve is turned “ON” or “OFF” by the TCM in response to signals sent from the PNP
switch, vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then
be shifted to the optimum position.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532403
On Board Diagnosis LogicINFOID:0000000003532404
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P1772 LC/B SOLENOID/CIRC” with CONSULT-II is detected when TCM detects
an improper voltage drop when it tries to operate the solenoid valve.
Possible CauseINFOID:0000000003532405
• Harness or connectors
(The solenoid circuit is open or shorted.)
• Low coast brake solenoid valve
DTC Confirmation ProcedureINFOID:0000000003532406
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 5
consecutive seconds.
Selector lever: “1” or “2”
Gear position: “1st” or “2nd” gear (LC/B ON/OFF)
5. If DTC is detected, go to AT-146, "
Diagnosis Procedure".
WITH GST
Follow the procedure “With CONSULT-II”.
Diagnosis ProcedureINFOID:0000000003532407
1.CHECK INPUT SIGNAL
With CONSULT-II
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
BCIA0031E

DTC P1772 LOW COAST BRAKE SOLENOID VALVE
AT-147
< SERVICE INFORMATION >
D
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1. Turn ignition switch “ON”.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Start the engine.
4. Read out the value of “ON OFF SOL” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2.CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-158
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3.DETECT MALFUNCTIONING ITEM
Check the following items:
• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT-210, "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2".
NG >> Repair or replace damaged parts.
4.CHECK DTC
Perform “DTC Confirmation Procedure”.
• Refer to AT-146, "
DTC Confirmation Procedure".
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
SCIA4794E