2008 INFINITI QX56 OBD port

P0735 5GR INCORRECT RATIOTM-61
< COMPONENT DIAGNOSIS >
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P0735 5GR INCORRECT RATIO
DescriptionINFOID:0000000001604070
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 shorted) but also by mechanical malfunction such as
control valve sticking, improper solenoid valve operation.
On Board Diagnosis LogicINFOID:0000000001604071
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0735” is detected when TCM detec ts any inconsistency in the actual gear ratio.
Possible CauseINFOID:0000000001604072
• 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 ProcedureINFOID:0000000001604073
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 “5TH GR FNCTN P0735” 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: “5” 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 P0735 is shown, refer to “ TM-116, "
DTC No. Index"”.
If “COMPLETED RESULT NG” is detected, go to TM-62, "
Diagnosis Procedure".
If “STOP VEHICLE” is detec ted, 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-
189, "Description".
-Perform TM-32, "
CONSULT-III Functi on (TRANSMISSION)" when not shifted from the 1GR to 5GR. (Nei-
ther “OK” nor “NG” are indicated.)
Revision: March 2010 2008 QX56

P0744 TORQUE CONVERTERTM-65
< COMPONENT DIAGNOSIS >
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P0744 TORQUE CONVERTER
DescriptionINFOID:0000000001604081
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.
CONSULT-III Reference Val ue in Data Monitor ModeINFOID:0000000001604082
On Board Diagnosis LogicINFOID:0000000001604083
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0744” with CONSULT-III is detected under the following conditions.
- When A/T cannot perform lock-up even if electrical circuit is good.
- When TCM detects as irregular by comparing difference value with slip rotation.
Possible CauseINFOID:0000000001604084
• Harness or connectors
(The solenoid circuit is open or shorted.)
• Torque converter clutch solenoid valve
• Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000001604085
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 and Select “TCC S/V FNCTN CHECK” of “DTC WORK SUPPORT” mode for “TRANSMIS- SION” with CONSULT-III and touch “START”.
2. Accelerate vehicle to more than 80 km/h (50 MPH) and maintain the following condition continuously until “TESTING” has turned to “COMPLETE”. (It will take approximately 30 seconds after “TESTING” shows.)
ACCELE POSI: More than 1.0/8 (at all times during step 4)
TCC SOLENOID: 0.4 - 0.6 A
Selector lever: “D” position
[Reference speed: Constant speed of more than 80 km/h (50 MPH)]
- Make sure “GEAR” shows “5”.
- For shift schedule, refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
- If “TESTING” does not appear on CONSULT-III for a long time, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0744 is shown, refer to applicable “TROUBLE DIAGNOSIS FOR
DTC”.
3. Make sure that “OK” is disp layed. (If “NG” is displayed, refer to “DIAGNOSTIC PROCEDURE”.)
Refer to TM-66, "
Diagnosis Procedure".
Refer to shift schedule, TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
WITH GST
Follow the procedure “With CONSULT-III”.
Item name Condition Display value (Approx.)
TCC SOLENOID When performing slip lock-up
0.2 - 0.4 A
When performing lock-up 0.4 - 0.6 A
Revision: March 2010 2008 QX56

TM-174
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for On Board Diagnosis (OBD) System of A/T and EngineINFOID:0000000001531485
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch “OFF” and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. Will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to an open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Be sure to route and secure th e harnesses properly after work. Interference of the harness with a
bracket, etc. May cause the MIL to light up due to a short circuit.
• Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to a malfunction of the EGR system or fuel injection system, etc.
• Be sure to erase the unnecessary malfunction informa tion (repairs completed) from the TCM and
ECM before returning the vehicle to the customer.
PrecautionINFOID:0000000001531486
NOTE:
If any malfunctions occur in the RE5R05A model tr ansmission, replace the entire transmission assem-
bly.
• Before connecting or disconn ecting the TCM harness connec-
tor, turn ignition switch “O FF” and disconnect negative bat-
tery cable. Because battery voltage is applied to TCM even if
ignition switch is turned “OFF”.
• After performing each TROUBLE DIAGNOSIS, perform “DTC
(Diagnostic Trouble Code) CONFIRMATION PROCEDURE”.
If the repair is completed the DTC should not be displayed in the
“DTC CONFIRMATION PROCEDURE”.
• Always use the specified brand of ATF. Refer to MA-12, "
Fluids and Lubricants".
• Use paper rags not cloth rags during work.
• After replacing the ATF, dispose of the waste oil using the methods prescribed by law, ordinance, etc.
• Before proceeding with disassembly, thoroughly clean the outside of the transmission. It is important to pre- vent the internal parts from becoming cont aminated by dirt or other foreign matter.
• Disassembly should be done in a clean work area.
• Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could interfere
with the operation of the transmission.
• Place disassembled parts in order for easier and proper assembly.
SEF289H
SEF217U
Revision: March 2010 2008 QX56

PRECAUTIONSTM-175
< PRECAUTION >
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• All parts should be carefully cleaned with a general purpose, non-flammable solvent before inspection or reassembly.
• Gaskets, seals and O-rings should be replaced any time the transmission is disassembled.
• It is very important to perform func tional tests whenever they are indicated.
• The valve body contains precision parts and requires extreme care when parts are removed and serviced. Place disassembled valve body parts in order for easier and proper assembly. Care will also prevent springs
and small parts from becoming scattered or lost.
• Properly installed valves, sleeves, plugs, etc. will slide along bores in valve body under their own weight.
• Before assembly, apply a coat of recommended ATF to all parts. Apply petroleum jelly to protect O-rings and
seals, or hold bearings and washers in pl ace during assembly. Do not use grease.
• Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.
• Clean or replace ATF cooler if excessive foreign material is found in oil pan or clogging strainer. Refer to TM-
182, "A/T Fluid Cooler Cleaning".
• After overhaul, refill the transmission with new ATF.
• When the A/T drain plug is removed, only some of the fluid is drained. Old A/T fluid will remain in torque con- verter and ATF cooling system.
Always follow the procedures under “Changing A/T Fluid” in the AT section when changing A/T fluid. Refer to
TM-180, "
Changing the A/T Fluid (ATF)".
Service Notice or PrecautionINFOID:0000000001531487
ATF COOLER SERVICE
• If A/T fluid contains fictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T fluid cooler mounted in the radiat or or replace the radiator. Flush cooler lines with
cleaning solvent and compressed air after repair. For A/T fluid cooler cleaning procedure, refer to TM-182,
"A/T Fluid Cooler Cleaning". For radiator replacement, refer to CO-15, "Removal and Installation".
CHECKING AND CHANGING A/T FLUID
• Increase ATF oil temperature to 80 °C (176° F) first, then check and adjust oil level at 65 °C (149° F).
NOTE:
The A/T has both water cooling and air cooling systems. The air cooling system has a bypass valve. When
ATF oil temperature is at or below 50 °C (122° F), it does not flow through the air cooled system. If A/T oil
level is adjusted without flow throughout the entir e system, the level will be 10mm lower than required.
Therefore, all piping should be filled with oil when adjusting level.
OBD-II SELF-DIAGNOSIS
• A/T self-diagnosis is performed by the TCM in combination with the ECM. Refer to the table on TM-32,
"CONSULT-III Function (TRANSMISSION)" for the indicator used to display each self-diagnostic result.
• The self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM memo- ries.
Always perform the procedure on TM-30, "
OBD-II Diagnostic Trouble Code (DTC)" to complete the
repair and avoid unnecessary blinking of the MIL.
For details of OBD-II, refer to TM-30
.
• Certain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For descrip tion and how to disconnect, refer to PG-65
.
Revision: March 2010 2008 QX56