Infiniti QX56 (Z62). Manual - part 1308

P1730 INTERLOCK

TM-141

< DTC/CIRCUIT DIAGNOSIS >

[7AT: RE7R01B]

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Diagnosis Procedure

INFOID:0000000006226860

1.

DETECT MALFUNCTIONING ITEM

Disassemble the A/T assembly to check component parts. Refer to 

TM-226, "Disassembly"

.

NOTE:
Check the component parts, referring to “Possible cause” in “DTC DETECTION LOGIC”. Refer to 

TM-140,

"DTC Logic"

.

Is the inspection result normal?

YES

>> Replace the control valve & TCM. Refer to 

TM-182, "Exploded View"

.

NO

>> Repair or replace damaged parts.

TM-142

< DTC/CIRCUIT DIAGNOSIS >

[7AT: RE7R01B]

P1734 7GR INCORRECT RATIO

P1734 7GR INCORRECT RATIO

Description

INFOID:0000000006226861

This malfunction is detected when the A/T does not shift into 7GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or shorted) but by mechanical malfunction such as control
valve sticking, improper solenoid valve operation, etc.

DTC Logic

INFOID:0000000006226862

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION:

• “

TM-143, "Diagnosis Procedure"

” must be performed before starting “DTC CONFIRMATION PROCE-

DURE”.

• Never perform “DTC CONFIRMATION PROCEDURE” before completing the repair, which may cause

secondary malfunction.

• Always drive vehicle at a safe speed.

1.

PRECONDITIONING

If “DTC CONFIRMATION PROCEDURE” is previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before performing the next test.

>> GO TO 2.

2.

CHECK ATF TEMPERATURE

 With CONSULT-III

1.

Start the engine.

2.

Select “ATF TEMP 1” in “Data Monitor” in “TRANSMISSION”.

3.

Check ATF temperature is in the following range.

 With GST

1.

Start the engine.

2.

Drive vehicle for approximately 5 minutes in urban areas.

Is ATF temperature within specified range?

YES

>> GO TO 3.

NO

>> Drive vehicle to warm ATF or stop engine to cool ATF.

3.

CHECK SYMPTOM (PART 1)

 With CONSULT-III

1.

Select “7TH GR FNCTN P1734” in “DTC & SRT confirmation” in “TRANSMISSION”.

2.

Drive vehicle with manual mode and maintain the following conditions.

DTC

Trouble diagnosis name

DTC is detected if...

Possible cause

P1734

Gear 7 Incorrect Ratio

The gear ratio is:
• 0.821 or more
• 0.729 or less

• Input clutch solenoid valve
• Direct clutch solenoid valve
• High and low reverse clutch 

solenoid valve

• Front brake solenoid valve
• Low brake solenoid valve
• 2346 brake solenoid valve
• Anti-interlock solenoid valve
• Each clutch and brake
• Output speed sensor
• Input speed sensor 1, 2
• Hydraulic control circuit

ATF TEMP 1

: 20

°

C (68

°

F) – 140

°

C (284

°

F)

P1734 7GR INCORRECT RATIO

TM-143

< DTC/CIRCUIT DIAGNOSIS >

[7AT: RE7R01B]

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3.

Keep the current driving status for 2 seconds or more if CONSULT-III screen changes from “OUT OF
CONDITION” to “TESTING”.

CAUTION:

When “TESTING” is not indicated on CONSULT-III for a long time, check “Self Diagnostic Results”
in “TRANSMISSION”. When a DTC other than “P1734” is detected, check the DTC. Refer to 

TM-78,

"DTC Index"

.

 With GST

1.

Drive vehicle and maintain the following conditions for 2 seconds or more.

2.

Check DTC.

Is  “OUT OF CONDITION”,  “STOP VEHICLE” or “COMPLETED RESULT NG” displayed? / Is “P1734”
detected?

YES-1 (OUT OF CONDITION)>>Perform “Step 3” again.
YES-2 (STOP VEHICLE)>>GO TO 4.
YES-3 (COMPLETED RESULT NG)>>Go to 

TM-143, "Diagnosis Procedure"

.

YES-4 (“P1734” is detected)>>Go to 

TM-143, "Diagnosis Procedure"

.

NO

>> GO TO 4.

4.

CHECK SYMPTOM (PART 2)

 With CONSULT-III

1.

Stop vehicle.

2.

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

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006226863

1.

DETECT MALFUNCTIONING ITEM

Disassemble the A/T assembly to check component parts. Refer to 

TM-226, "Disassembly"

.

NOTE:
Check the component parts, referring to “Possible cause” in “DTC DETECTION LOGIC”. Refer to 

TM-142,

"DTC Logic"

.

Is the inspection result normal?

YES

>> Replace the control valve & TCM. Refer to 

TM-182, "Exploded View"

.

NO

>> Repair or replace damaged parts.

GEAR

: 7th

ACCELE POSI

: 0.7/8 or more

VEHICLE SPEED

: 10 km/h (7 MPH) or more

Selector lever

: “M” position

Gear position

: 7th

Accelerator pedal opening

: 0.7/8 or more

Vehicle speed

: 10 km/h (7 MPH) or more

TM-144

< DTC/CIRCUIT DIAGNOSIS >

[7AT: RE7R01B]

P1815 M-MODE SWITCH

P1815 M-MODE SWITCH

DTC Logic

INFOID:0000000006226864

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If “DTC CONFIRMATION PROCEDURE” is previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before performing the next test.

>> GO TO 2.

2.

CHECK DTC DETECTION

 With CONSULT-III

1.

Turn ignition switch ON.

2.

Select “SLCT LVR POSI” and “MANU MODE SW” in “Data Monitor” in “TRANSMISSION”.

3.

Maintain the following each conditions more than 2 seconds.

4.

Perform “Self Diagnostic Results” in “TRANSMISSION”.

Is “P1815” detected?

YES

>> Go to 

TM-144, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006226865

1.

CHECK MANUAL MODE SWITCH CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect A/T shift selector connector.

3.

Turn ignition switch ON.

4.

Check voltage between A/T shift selector vehicle side harness connector terminals.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

CHECK MANUAL MODE SWITCH

DTC

Trouble diagnosis name

DTC is detected if...

Possible cause

P1815

Manual Mode Switch Circuit

TCM monitors manual mode, 
non manual mode, up or down 
switch signal, and detects as ir-
regular when impossible input 
pattern occurs 2 second or 
more.

• Harness or connectors

(These switches circuit is 
open or shorted.)

• Manual mode switch

SLCT LVR POSI

: D

MANU MODE SW

: ON

A/T shift selector vehicle side harness connector

Voltage (Approx.)

Connector

Terminal

+

−

M57

1

4

Battery voltage

2

3

5