Infiniti QX56 (JA60). Manual - part 938

TM-54

< COMPONENT DIAGNOSIS >

P0725 ENGINE SPEED

NG

>> Check the ignition signal circuit. Refer to 

EC-407, "Diagnosis Procedure"

.

3.

CHECK DTC

Perform "DTC Confirmation Procedure". 

• Refer to 

TM-53, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 4.

4.

CHECK TCM POWER SUPPLY AND GROUND CIRCUIT

Check TCM power supply and ground circuit. Refer to 

TM-94, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 5.

NG

>> Repair or replace damaged parts.

5.

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 

TM-172, "Control Valve with TCM and A/T Fluid

Temperature Sensor 2 and Plug"

.

NG

>> Repair or replace damaged parts.

P0731 1GR INCORRECT RATIO

TM-55

< COMPONENT DIAGNOSIS >

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P0731 1GR INCORRECT RATIO

Description

INFOID:0000000005148568

This malfunction is detected when the A/T does not shift into 1GR position as instructed by TCM. This is not

only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as

control valve sticking, improper solenoid valve operation.

On Board Diagnosis Logic

INFOID:0000000005148569

• This is an OBD-II self-diagnostic item.

• Diagnostic trouble code “P0731 1GR INCORRECT RATIO” is detected when TCM detects any inconsis-

tency in the actual gear ratio.

Possible Cause

INFOID:0000000005148570

• Harness or connectors 

(Solenoid circuits are open or shorted.)

• Input clutch solenoid valve

• Front brake solenoid valve

• Direct clutch solenoid valve

• High and low reverse clutch solenoid valve

• Each clutch

• Hydraulic control circuit

DTC Confirmation Procedure

INFOID:0000000005148571

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 the engine and select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.

2. Make sure that “ATF TEMP 1” is within the following range.

ATF TEMP 1: 20

°C – 140°C

If out of range, drive vehicle to warm ATF or stop engine to cool ATF.

3. Select “1ST GR FNCTN P0731” of “DTC WORK SUPPORT” mode for “TRANSMISSION” with CON-

SULT-III.

4. Drive vehicle and maintain the following conditions.

VEHICLE SPEED: 10 km/h (6 MPH) or more

ACCELE POSI: 0.6/8 or more

ENGINE SPEED: INPUT SPEED 

− 50 rpm or more

INPUT SPEED: 300 rpm or more

GEAR: “1” position

MANU MODE SW: ON

5. Keep the current driving status for at least 5 consecutive seconds if CONSULT-III screen changes from

“OUT OF CONDITION” to “TESTING”.

CAUTION:

If “TESTING” does not appear on CONSULT-III for a long time, select “SELF-DIAG RESULTS”. In

case a 1st trip DTC other than P0731 is shown, refer to “

TM-119, "DTC No. Index"

”.

If “COMPLETED RESULT NG” is detected, go to 

TM-56, "Diagnosis Procedure"

.

If “STOP VEHICLE” is detected, go to the following step.

6. Stop vehicle.

7. Drive vehicle in “D” position allowing it to shift from 1GR to 5GR and check shift timing and shift shock.

-

Touch “OK” to complete the inspection when normally shifted from the 1GR to 5GR.

-

Touch “NG” when an unusual shift shock, etc. occurs in spite of shifting from the 1GR to 5GR. Go to 

TM-

159, "Description"

.

-

Perform 

TM-32, "CONSULT-III Function (TRANSMISSION)"

 when not shifted from the 1GR to 5GR. (Nei-

ther “OK” nor “NG” are indicated.)

TM-56

< COMPONENT DIAGNOSIS >

P0731 1GR INCORRECT RATIO

Diagnosis Procedure

INFOID:0000000005148572

1.

CHECK CAN COMMUNICATION LINE

Perform self-diagnosis. Refer to 

TM-32, "CONSULT-III Function (TRANSMISSION)"

.

Is a malfunction in the CAN communication indicated in the results?

YES

>> Check CAN communication line. Refer to 

TM-40, "Diagnosis Procedure"

.

NO

>> GO TO 2.

2.

CHECK TCM POWER SUPPLY AND GROUND CIRCUIT

Check TCM power supply and ground circuit. Refer to 

TM-94, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace damaged parts.

3.

DETECT MALFUNCTION ITEM

Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG

OK

>> GO TO 4.

NG

>> Repair or replace damaged parts.

4.

REPLACE CONTROL VALVE WITH TCM

1. Replace control valve with TCM. Refer to 

TM-172, "Control Valve with TCM and A/T Fluid Temperature

Sensor 2 and Plug"

.

2. Perform 

TM-55, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> Confirm malfunction phenomena by “ROAD TEST” to repair malfunctioning part. Refer to 

TM-159,

"Description"

.

P0732 2GR INCORRECT RATIO

TM-57

< COMPONENT DIAGNOSIS >

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P0732 2GR INCORRECT RATIO

Description

INFOID:0000000005148573

This malfunction is detected when the A/T does not shift into 2GR position as instructed by TCM. This is not

only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as

control valve sticking, improper solenoid valve operation.

On Board Diagnosis Logic

INFOID:0000000005148574

• This is an OBD-II self-diagnostic item.

• Diagnostic trouble code “P0732 2GR INCORRECT RATIO” detected when TCM detects any inconsistency

in the actual gear ratio.

Possible Cause

INFOID:0000000005148575

• Harness or connectors 

(Solenoid circuits are open or shorted.)

• Input clutch solenoid valve

• Front brake solenoid valve

• Direct clutch solenoid valve

• High and low reverse clutch solenoid valve

• Each clutch

• Hydraulic control circuit

DTC Confirmation Procedure

INFOID:0000000005148576

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 the engine and select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.

2. Make sure that “ATF TEMP 1” is within the following range.

ATF TEMP 1: 20

°C – 140°C

If out of range, drive vehicle to warm ATF or stop engine to cool ATF.

3. Select “2ND GR FNCTN P0732” of “DTC WORK SUPPORT” mode for “TRANSMISSION” with CON-

SULT-III.

4. Drive vehicle and maintain the following conditions.

VEHICLE SPEED: 10 km/h (6 MPH) or more

ACCELE POSI: 0.6/8 or more

ENGINE SPEED: INPUT SPEED 

− 50 rpm or more

INPUT SPEED: 300 rpm or more

GEAR: “2” position

MANU MODE SW: ON

5. Keep the current driving status for at least 5 consecutive seconds if CONSULT-III screen changes from

“OUT OF CONDITION” to “TESTING”.

CAUTION:

If “TESTING” does not appear on CONSULT-III for a long time, select “SELF-DIAG RESULTS”. In

case a 1st trip DTC other than P0732 is shown, refer to “

TM-119, "DTC No. Index"

”.

If “COMPLETED RESULT NG” is detected, go to 

TM-58, "Diagnosis Procedure"

.

If “STOP VEHICLE” is detected, go to the following step.

6. Stop vehicle.

7. Drive vehicle in “D” position allowing it to shift from 1GR to 5GR and check shift timing and shift shock.

-

Touch “OK” to complete the inspection when normally shifted from the 1GR to 5GR.

-

Touch “NG” when an unusual shift shock, etc. occurs in spite of shifting from the 1GR to 5GR. Go to 

TM-

159, "Description"

.

-

Perform 

TM-32, "CONSULT-III Function (TRANSMISSION)"

 when not shifted from the 1GR to 5GR. (Nei-

ther “OK” nor “NG” are indicated.)