Infiniti FX35 / FX45. Manual - part 53

AT-140

< SERVICE INFORMATION >

DTC P1730 A/T INTERLOCK

4.

Perform self-diagnosis. Refer to 

AT-91, "Diagnosis Procedure without CONSULT-III"

.

 OK or NG

OK

>> GO TO 2.

NG

>> Check low coast brake solenoid valve circuit and function. Refer to 

AT-151

, 

AT-153

.

2.

CHECK DTC

Perform 

AT-139, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 3.

3.

CHECK TCM POWER SUPPLY AND GROUND CIRCUIT

Check TCM power supply and ground circuit. Refer to 

AT-160

.

OK or NG

OK

>> GO TO 4.

NG

>> Repair or replace damaged parts.

4.

DETECT MALFUNCTIONING ITEM

Check 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-215, "Control Valve with TCM and A/T Fluid Tem-

perature Sensor 2"

.

NG

>> Repair or replace damaged parts.

DTC P1731 A/T 1ST ENGINE BRAKING

AT-141

< SERVICE INFORMATION >

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DTC P1731 A/T 1ST ENGINE BRAKING

Description

INFOID:0000000001327253

Fail-safe function to prevent sudden decrease in speed by engine brake other than at M1 position.

CONSULT-III Reference Value in Data Monitor Mode

INFOID:0000000001327254

On Board Diagnosis Logic

INFOID:0000000001327255

Diagnostic trouble code “P1731 A/T 1ST E/BRAKING” with CONSULT-III or 13th judgement 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 Cause

INFOID:0000000001327256

• Harness or connectors

(Sensor circuit is open or shorted.)

• Low coast brake solenoid valve
• ATF pressure switch 2

DTC Confirmation Procedure

INFOID:0000000001327257

CAUTION:

• Always drive vehicle at a safe speed.
• Be careful not to rev engine into red zone on the tachometer.
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-141, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000001327258

1.

CHECK INPUT SIGNALS

 With CONSULT-III

1.

Start the 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”.

Item name

Condition 

Display value

ON OFF SOL

Low coast brake engaged. Refer to 

AT-18

.

ON

Low coast brake disengaged. Refer to 

AT-18

.

OFF

ATF PRES SW 2

Low coast brake engaged. Refer to 

AT-18

.

ON

Low coast brake disengaged. Refer to 

AT-18

.

OFF

AT-142

< SERVICE INFORMATION >

DTC P1731 A/T 1ST ENGINE BRAKING

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-160

.

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 the control valve with TCM. Refer to 

AT-215, "Control Valve with TCM and A/T Fluid Tem-

perature Sensor 2"

.

NG

>> Repair or replace damaged parts.

4.

CHECK DTC

Perform 

AT-141, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 2.

Item name

Condition 

Display value 

ON OFF SOL

Low coast brake engaged. Refer to 

AT-18

.

ON

Low coast brake disengaged. Refer to 

AT-18

.

OFF

ATF PRES SW 2

Low coast brake engaged. Refer to 

AT-18

.

ON

Low coast brake disengaged. Refer to 

AT-18

.

OFF

DTC P1752 INPUT CLUTCH SOLENOID VALVE

AT-143

< SERVICE INFORMATION >

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DTC P1752 INPUT CLUTCH SOLENOID VALVE

Description

INFOID:0000000001327259

Input clutch 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 Value in Data Monitor Mode

INFOID:0000000001327260

On Board Diagnosis Logic

INFOID:0000000001327261

Diagnostic trouble code “P1752 I/C SOLENOID/CIRC” with CONSULT-III or 5th judgement 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 Cause

INFOID:0000000001327262

• Harness or connectors

(Solenoid circuit is open or shorted.)

• Input clutch solenoid valve 

DTC Confirmation Procedure

INFOID:0000000001327263

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 “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” (I/C 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-143, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III”.

Diagnosis Procedure

INFOID:0000000001327264

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 the engine.

Item name

Condition 

Display value (Approx.) 

I/C SOLENOID

Input clutch disengaged. Refer to 

AT-18

.

0.6 - 0.8 A

Input clutch engaged. Refer to 

AT-18

.

0  -  0.05  A