2011 INFINITI QX56 Engine mechanical

TM-124
< DTC/CIRCUIT DIAGNOSIS >[7AT: RE7R01B]
P0734 4GR INCORRECT RATIO
P0734 4GR INCORRECT RATIO
DescriptionINFOID:0000000006226830
This malfunction is detected when the A/T does not shift
into 4GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or s horted) but by mechanical malfunction such as control
valve sticking, improper solenoid valve operation, etc.
DTC LogicINFOID:0000000006226831
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION:
“ TM-125, "
Diagnosis Procedure"” must be performed before star ting “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 c onducted, 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 “4TH GR FNCTN P0734” 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
P0734 Gear 4 Incorrect Ratio The gear ratio is:
 1.496 or more
 1.328 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 co ntrol circuit
ATF TEMP 1 : 20 °C (68 °F) – 140 °C (284 °F)
Revision: 2010 May2011 QX56

TM-126
< DTC/CIRCUIT DIAGNOSIS >[7AT: RE7R01B]
P0735 5GR INCORRECT RATIO
P0735 5GR INCORRECT RATIO
DescriptionINFOID:0000000006226833
This malfunction is detected when the A/T does not shift
into 5GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or s horted) but by mechanical malfunction such as control
valve sticking, improper solenoid valve operation, etc.
DTC LogicINFOID:0000000006226834
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION:
“ TM-127, "
Diagnosis Procedure"” must be performed before star ting “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 c onducted, 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 “5TH GR FNCTN P0735” 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
P0735 Gear 5 Incorrect Circuit The gear ratio is:
 1.060 or more
 0.940 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 co ntrol circuit
ATF TEMP 1 : 20 °C (68 °F) – 140 °C (284 °F)
Revision: 2010 May2011 QX56

P0744 TORQUE CONVERTERTM-129
< DTC/CIRCUIT DIAGNOSIS > [7AT: RE7R01B]
C
EF
G H
I
J
K L
M A
B
TM
N
O P
P0744 TORQUE CONVERTER
DescriptionINFOID:0000000006226838
This malfunction is detected when the A/T does not lock-up. 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, etc.
DTC LogicINFOID:0000000006226839
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION:
Always drive vehicle at a safe speed.
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” is previously c onducted, 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. Start the engine.
2. Select “MANU MODE SW”, “GEAR” and “VEHICLE SPEED” in “Data Monitor” in “TRANSMISSION”.
3. Drive vehicle and maintain the following conditions for 10 seconds or more. NOTE:
Driving the vehicle uphill (increased engine load) will hel p maintain the driving conditions required for this
test.
4. Perform “Self Diagnostic Resu lts” in “TRANSMISSION”.
With GST
Follow the procedure “With CONSULT-III”.
Is
“P0744” detected?
YES >> Go to TM-129, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006226840
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 “Possibl e cause” in “DTC DETECTION LOGIC”. Refer to TM-129,
"DTC Logic".
Is the inspection result normal?
YES >> Replace the control valve & TCM. Refer to TM-182, "Exploded View".
DTC Trouble diagnosis name DTC is detected if... Possible cause
P0744 Torque Converter Clutch Circuit
Intermittent The lock-up is not performed in
spite of within the lock-up area.  Harness or connectors
 Torque converter clutch sole-
noid valve
 Torque converter
 Input speed sensor 1, 2
 Hydraulic control circuit
MANU MODE SW : ON
GEAR : 2nd
VEHICLE SPEED : 40 km/h (25 MPH) or more
Revision: 2010 May2011 QX56

TM-134
< DTC/CIRCUIT DIAGNOSIS >[7AT: RE7R01B]
P0780 SHIFT
P0780 SHIFT
DescriptionINFOID:0000000006226847
The TCM detects the malfunction of low brake solenoid valv
e. 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, etc.
DTC LogicINFOID:0000000006226848
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION:
“ TM-134, "
Diagnosis Procedure"” must be performed before star ting “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 c onducted, 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. Start the engine.
2. Select “SLCT LVR POSI”, “ACCELE POSI” and “G EAR” in “Data Monitor” in “TRANSMISSION”.
3. Drive vehicle and maintain the following conditions.
4. Perform “Self Diagnostic Results” in “TRANSMISSION”.
With GST
Follow the procedure “With CONSULT-III”.
Is
“P0780” detected?
YES >> Go to TM-134, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006226849
1.DETECT MALFUNCTIONING ITEM
Disassemble the A/T assembly to check component parts. Refer to TM-226, "
Disassembly".
NOTE:
DTC Trouble diagnosis name DTC is detected if... Possible cause
P0780 Shift Error  When shifting from 3GR to
4GR with the selector lever in
“D” position, the gear ratio
does not shift to 1.412 (gear
ratio of 4th).
 When shifting from 5GR to 6GR or 6GR to 7GR, the en-
gine speed exceeds the pre-
scribed speed.  Anti-interlock solenoid valve
 Low brake solenoid valve
 Hydraulic control circuit
SLCT LVR POSI : D
ACCELE POSI : More than 1.0/8
GEAR : 3rd
→ 4th
Revision: 2010 May2011 QX56

TM-142
< DTC/CIRCUIT DIAGNOSIS >[7AT: RE7R01B]
P1734 7GR INCORRECT RATIO
P1734 7GR INCORRECT RATIO
DescriptionINFOID: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 s horted) but by mechanical malfunction such as control
valve sticking, improper solenoid valve operation, etc.
DTC LogicINFOID:0000000006226862
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION:
“ TM-143, "
Diagnosis Procedure"” must be performed before star ting “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 c onducted, 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)
Revision: 2010 May2011 QX56