DTC P1731 A/T 1ST ENGINE BRAKING
AT-143
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Revision: 2006 November2007 350Z
DTC P1731 A/T 1ST ENGINE BRAKINGPFP:00000
DescriptionNCS00056
Fail-safe function to prevent sudden decrease in speed by engine brake other than at M1 position.
CONSULT-III Reference ValueNCS00057
On Board Diagnosis LogicNCS00058
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “P1731 A/T 1ST E/BRAKING” with CONSULT-III or 13th judgment flicker without
CONSULT-III is detected under the following conditions.
–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 M1 position.
Possible CauseNCS00059
Harness or connectors
(The sensor circuit is open or shorted.)
Low coast brake solenoid valve
ATF pressure switch 2
DTC Confirmation ProcedureNCS0005A
CAUTION:
Always drive vehicle at a safe speed.
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-III
1. Turn ignition switch ON.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III
and check monitor “ENGINE SPEED”, “MANU MODE SW” and “GEAR”.
3. Touch “START”.
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 2 consecutive seconds.
ENGINE SPEED: 1,200 rpm
MANU MODE SW: ON
GEAR: “1” position
6. If DTC is detected, go to AT- 1 4 4 , "
Diagnostic Procedure" .
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
AT-144
DTC P1731 A/T 1ST ENGINE BRAKING
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0005B
1. CHECK INPUT SIGNALS
With CONSULT-III
1. Start engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Drive vehicle in the “M” 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- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 4 3 , "
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- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
DTC P1757 FRONT BRAKE SOLENOID VALVE
AT-147
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Revision: 2006 November2007 350Z
DTC P1757 FRONT BRAKE SOLENOID VALVEPFP:31940
DescriptionNCS0005O
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-III Reference ValueNCS0005P
On Board Diagnosis LogicNCS0005Q
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P1757 FR/B SOLENOID/CIRC” with CONSULT-III or 6th judgment flicker without
CONSULT-III 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 CauseNCS0005R
Harness or connectors
(Solenoid circuit is open or shorted.)
Front brake solenoid valve
DTC Confirmation ProcedureNCS0005S
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 preforming the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III
and check monitor “ACCELE POSI”, “SLCT LVR POSI” and “GEAR”.
3. Touch “START”.
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 5 consecutive seconds.
ACCELE POSI: 1.5/8 – 2.0/8
SLCT LVR POSI: “D” position
GEAR: “3” “4” (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
6. If DTC is detected go to AT- 1 4 8 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III”.
Item name Condition Display value (Approx.)
FR/B SOLENOIDFront brake engaged. Refer to AT- 1 9
. 0.6 – 0.8 A
Front brake disengaged. Refer to AT- 1 9
. 0 – 0.05 A
AT-148
DTC P1757 FRONT BRAKE SOLENOID VALVE
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0005T
1. CHECK INPUT SIGNAL
With CONSULT-III
1. Turn ignition switch ON.
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
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- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 4 7 , "
DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name ConditionDisplay value
(Approx.)
FR/B SOLENOIDFront brake engaged. Refer to AT- 1 9
. 0.6 – 0.8 A
Front brake disengaged. Refer to AT- 1 9
. 0 – 0.05 A
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
AT-153
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Revision: 2006 November2007 350Z
DTC P1772 LOW COAST BRAKE SOLENOID VALVEPFP:31940
DescriptionNCS0006O
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-III Reference ValueNCS0006P
On Board Diagnosis LogicNCS0006Q
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P1772 LC/B SOLENOID/CIRC” with CONSULT-III or 7th judgment flicker without
CONSULT-III is detected when TCM detects an improper voltage drop when it tries to operate the sole-
noid valve.
Possible CauseNCS0006R
Harness or connectors
(Solenoid circuit is open or shorted.)
Low coast brake solenoid valve
DTC Confirmation ProcedureNCS0006S
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-III
1. Turn ignition switch ON.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III
and check monitor “MANU MODE SW” and “GEAR”.
3. Touch “START”.
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 5 consecutive seconds.
MANU MODE SW: ON
GEAR: “1” or “2” (LC/B ON/OFF)
6. If DTC is detected, go to AT- 1 5 4 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III”.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
AT-154
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0006T
1. CHECK INPUT SIGNAL
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start 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- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 5 3 , "
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- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
AT-155
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Revision: 2006 November2007 350Z
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionNCS0006U
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.
This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical mal-
function such as control valve sticking, improper solenoid valve operation.
CONSULT-III Reference ValueNCS0006V
On Board Diagnosis LogicNCS0006W
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P1774 LC/B SOLENOID FNCT” with CONSULT-III or 7th judgment flicker with-
out CONSULT-III 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 2 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 2 is irregular
during releasing accelerator pedal (Other than during shift change)
Possible CauseNCS0006X
Harness or connectors
(The solenoid and switch circuits are open or shorted.)
Low coast brake solenoid valve
ATF pressure switch 2
DTC Confirmation ProcedureNCS0006Y
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-III
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
MANU MODE SW: ON
GEAR: “1” or “2” (LC/B ON/OFF)
3. Perform step 2 again.
4. Turn ignition switch OFF, then perform step 1 to 3 again.
5. Check “SELF-DIAG RESULTS” mode for “TRANSMISSION” with CONSULT-III.
If DTC (P1774) is detected, refer to AT- 1 5 6 , "
Diagnostic Procedure" .
If DTC (P1772) is detected, go to AT- 1 5 4 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III”.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
AT-156
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0006Z
1. CHECK INPUT SIGNALS
With CONSULT-III
1. Start engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Drive vehicle in the manual mode (“1” or “2” gear), and confirm the ON/OFF actuation of the “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- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 5 5 , "
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- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF