INFINITI QX56 2010 Factory Service Manual

TM-116
< ECU DIAGNOSIS >
TCM
AADIA0124GB
Revision: April 20092010 QX56

TCM
TM-117
< ECU DIAGNOSIS >
C EF
G H
I
J
K L
M A
B
TM
N
O P
Fail-SafeINFOID:0000000005148690
The TCM has an electrical fail-safe mode. This mode make s it possible to operate even if there is an error in a
main electronic control input/output signal circuit.
The TCM has an electrical fail-safe mode. This mode make s it possible to operate even if there is an error in a
main electronic control input/output signal circuit. In fail-safe mode the transmission is fixed in 2GR, 4GR or
5GR (depending on the breakdown position), so the customer should feel “slipping” or “poor acceleration”.
ABDIA0053GB
Revision: April 20092010 QX56

TM-118
< ECU DIAGNOSIS >
TCM
Even when the electronic circuits are normal, under special conditions (for example, when slamming on the
brake with the wheels spinning drastically and stopping the tire rotation), the transmission can go into fail-safe
mode. If this happens, switch “OFF” the ignition switch for 10 seconds, then switch it “ON” again to return to
the normal shift pattern. Therefore, the customer's v ehicle has returned to normal, so handle according to the
“diagnostics flow” (Refer to TM-5, "
Work Flow").
FAIL-SAFE FUNCTION
If any malfunction occurs in a sensor or solenoid, th is function controls the A/T to mark driving possible.
Output Speed Sensor
• Signals are input from two systems - from output speed sensor installed on the transmission and from com-
bination meter so normal driving is possible even if there is a malfunction in one of the systems. And if output
speed sensor has unusual cases, 5GR is prohibited.
Accelerator Peda l Position Sensor
• If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM according
to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow sys-
tems, the engine speed is fixed by ECM to a pre-determined engine speed to make driving possible.
Throttle Position Sensor
• If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM according
to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow sys-
tems, the accelerator opening angle is controlled by the idle signal sent from the ECM which is based on
input indicating either idle condition or off-idle condition (pre-determined accelerator opening) in order to
make driving possible.
Transmission Range Switch
• In the unlikely event that a malfunction signal enters t he TCM, the position indicator is switched “OFF”, the
starter relay is switched “OFF” (starter starting is disabled), the back-up lamp relay switched “OFF” (back-up
lamp is OFF) and the position is fixed to the “D” position to make driving possible.
Starter Relay
• The starter relay is switched “OFF”. (Starter starting is disabled.)
Interlock
• If there is an interlock judgment malfunction, the trans mission is fixed in 2GR to make driving possible.
NOTE:
When the vehicle is driven fixed in 2GR, a input speed sensor malfunction is displayed, but this is
not a input speed sensor malfunction.
• When the interlock is detected at the 3GR or more, it is locked at the 2GR.
1st Engine Braking
• When there is an 1st engine brake judgment malfunction, the low coast brake solenoid is switched “OFF” to
avoid the engine brake operation.
Line Pressure Solenoid
• The solenoid is switched “OFF” and the line pressure is set to the maximum hydraulic pressure to make driv- ing possible.
Torque Converter Clutch Solenoid
• The solenoid is switched “OFF” to release the lock-up.
Low Coast Brake Solenoid
• When a (electrical or functional) malfunction occurs, in order to make driving possible, the engine brake isnot applied in 1GR and 2GR.
Input Clutch Solenoid
• If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4GR to make driving possible.
Direct Clutch Solenoid
• If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4GR to make driving possible.
Front Brake Solenoid
• If a (electrical or functional) malfunction occurs with the solenoid “ON”, in order to make driving possible, the
A/T is held in 5GR; if the solenoid is OFF, 4GR.
Revision: April 20092010 QX56

TCM
TM-119
< ECU DIAGNOSIS >
C EF
G H
I
J
K L
M A
B
TM
N
O P
High and Low Revers
e Clutch Solenoid
• If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4GR to make driving possible.
Input Speed Sensor 1 or 2
• The control is the same as if there were no input speed sensors, 5GR is prohibited.
DTC Inspection Priority ChartINFOID:0000000005148691
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 is displayed with other DTCs, first pe rform the trouble diagnosis for DTC U1000. Refer to
TM-40, "
Diagnosis Procedure".
DTC No. IndexINFOID:0000000005148692
NOTE:
If DTC U1000 is displayed with other DTC, first pe rform the trouble diagnosis for DTC U1000. Refer to
TM-40, "
Diagnosis Procedure".
Priority Detected items (DTC)
1 U1000 CAN COMM CIRCUIT
2 Except above
DTC
Items
(CONSULT- III screen terms) Reference
OBD- II
Except OBD- II
CONSULT- III GST (*1) CONSULT- III only
“TRANSMISSION”
— P0615STARTER RELAY TM-41
P0700P0700TRANSMISSION CONTROL TM-44
P0705P0705T/M RANGE SWITCH A TM-45
P0710P1710FLUID TEMP SENSOR TM-73
P0717P0717INPUT SPEED SENSOR A TM-48
P0720P0720OUTPUT SPEED SENSOR TM-51
—P0725ENGINE SPEED TM-53
P0731P07311GR INCORRECT RATIO TM-56
P0732P07322GR INCORRECT RATIO TM-58
P0733P07333GR INCORRECT RATIO TM-60
P0734P07344GR INCORRECT RATIO TM-62
P0735P07355GR INCORRECT RATIO TM-64
P0740P0740TORQUE CONVERTER TM-65
P0744 P0744 TORQUE CONVERTER TM-68
P0745P0745PC SOLENOID A TM-69
—P1705TP SENSOR TM-71
—P1721VEHICLE SPEED SIGNAL TM-76
P1730P1730INTERLOCK TM-78
—P17311GR E/BRAKING TM-80
P1752P1752INPUT CLUTCH SOLENOID TM-82
P1757P1757FR BRAKE SOLENOID TM-84
P1762P1762DRCT CLUTCH SOLENOID TM-86
P1767P1767HLR CLUTCH SOLENOID TM-88
Revision: April 20092010 QX56

TM-120
< ECU DIAGNOSIS >
TCM
*1: These numbers are prescribed by SAE J2012.
*2: These malfunctions cannot be displayed MIL if another malfunction is assigned to MIL.
DTC Alphabetical IndexINFOID:0000000005148693
NOTE:
If DTC U1000 is displayed with other DTC, first perform the trouble diagnosis for DTC U1000. Refer to
TM-40, "
Diagnosis Procedure".
*1: These numbers are prescribed by SAE J2012.
*2: These malfunctions cannot be displayed MIL if another malfunction is assigned to MIL. P1772
P1772L C BRAKE SOLENOID TM-90
P1774 (2*) P1774 L C BRAKE SOLENOID TM-93
U1000U1000CAN COMM CIRCUIT TM-40
DTC
Items
(CONSULT- III screen terms) Reference
OBD- II
Except OBD- II
CONSULT- III GST (*1) CONSULT- III only
“TRANSMISSION”
Items
(CONSULT- III screen terms) DTC
Reference
OBD- II
Except OBD- II
CONSULT- III GST (*1) CONSULT- III only “TRANS-
MISSION”
1ST E/BRAKING —P1731TM-80
1GR INCORRECT RATIO P0731P0731TM-56
2GR INCORRECT RATIO P0732P0732TM-58
3GR INCORRECT RATIO P0733P0733TM-60
4GR INCORRECT RATIO P0734P0734TM-62
5GR INCORRECT RATIO P0735P0735TM-64
INTERLOCK P1730P1730TM-78
TORQUE CONVERTER P0744 P0744 TM-68
FLUID TEMP SENSOR P0710P1710TM-73
CAN COMM CIRCUIT U1000U1000TM-40
DRCT CLUTCH SOLENOID P1762P1762 TM-86
ENGINE SPEED —P0725TM-53
FR BRAKE SOLENOID P1757P1757TM-84
HLR CLUTCH SOLENOID P1767P1767TM-88
INPUT CLUTCH SOLENOID P1752P1752TM-82
PC SOLENOID A P0745P0745TM-69
L C BRAKE SOLENOID P1772P1772TM-90
L C BRAKE SOLENOID P1774 P1774 TM-93
T/M RANGE SWITCH A P0705P0705TM-45
STARTER RELAY —P0615TM-41
TORQUE CONVERTER P0740P0740TM-65
TRANSMISSION CONTROL P0700P0700TM-44
TP SENSOR —P1705TM-71
INPUT SPEED SENSOR A P0717P0717TM-48
VEHICLE SPEED SIGNAL —P1721TM-76
OUTPUT SPEED SENSOR P0720P0720TM-51
Revision: April 20092010 QX56

SYSTEM SYMPTOMTM-121
< SYMPTOM DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
SYMPTOM DIAGNOSIS
SYSTEM SYMPTOM
Symptom TableINFOID:0000000005148715
• The diagnostics item numbers s how the sequence for inspection. Inspect in order from item 1.
• Overhaul and inspect inside the A/T only if A/T fluid condition is NG. Refer to TM-148, "
Checking the
A/T Fluid (ATF)".
No. ItemsSymptom Condition Diagnostic ItemReference
page
1
Shift
Shock Large shock. (“N”
→“
D” position) ON vehicle1. Engine idle speed
EC-17
2. Engine speed signalTM-53
3. Accelerator pedal position sensorTM-71
4. Control cable adjustmentTM-164
5. ATF temperature sensor TM-73
6. Front brake solenoid valveTM-84
7. CAN communication line LAN-4
8. Fluid level and stateTM-148
9. Line pressure testTM-157
10. Control valve with TCMTM-172
OFF vehicle11. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to
TM-8, TM-9 . TM-204
2 Shock is too large
when changing D1→
D
2. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. Direct clutch solenoid valve TM-86
4. CAN communication line LAN-4
5. Engine speed signalTM-53
6. Input speed sensorTM-48
7. Output speed sensor and vehicle speed signalTM-50,
TM-76
8. Fluid level and state TM-148
9. Control valve with TCMTM-172
OFF vehicle 10. Direct clutch TM-239
3Shock is too large
when changing D2→
D
3. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. High and low reverse clutch solenoid valve TM-88
4. CAN communication line LAN-4
5. Engine speed signalTM-53
6. Input speed sensorTM-48
7. Output speed sensor and vehicle speed signalTM-50,
TM-76
8. Fluid level and state TM-148
9. Control valve with TCMTM-172
OFF vehicle 10. High and low reverse clutch TM-237
Revision: April 20092010 QX56

TM-122
< SYMPTOM DIAGNOSIS >
SYSTEM SYMPTOM
4Shift
Shock Shock is too large
when changing D3→
D
4. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. Input clutch solenoid valve TM-82
4. CAN communication line LAN-4
5. Engine speed signalTM-53
6. Input speed sensorTM-48
7. Output speed sensor and vehicle speed signalTM-50,
TM-76
8. Fluid level and state TM-148
9. Control valve with TCMTM-172
OFF vehicle 10. Input clutch TM-227
5Shock is too large
when changing D4→
D
5. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. Front brake solenoid valve TM-84
4. CAN communication line LAN-4
5. Engine speed signalTM-53
6. Input speed sensorTM-48
7. Output speed sensor and vehicle speed signalTM-50,
TM-76
8. Fluid level and state TM-148
9. Control valve with TCMTM-172
OFF vehicle10. Front brake (brake band)
TM-19211. Input clutchTM-227
6Shock is too large for
downshift when accel-
erator pedal is
pressed. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. CAN communication line LAN-4
4. Engine speed signalTM-53
5. Input speed sensorTM-48
6. Output speed sensor and vehicle speed signalTM-50,
TM-76
7. Fluid level and state TM-148
8. Control valve with TCMTM-172
OFF vehicle9. Front brake (brake band)
TM-19210. Input clutchTM-227
11. High and low reverse clutchTM-237
12. Direct clutchTM-239
No. ItemsSymptom Condition Diagnostic ItemReference
page
Revision: April 20092010 QX56

SYSTEM SYMPTOMTM-123
< SYMPTOM DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
7
Shift
Shock Shock is too large for
upshift when accelera-
tor pedal is released.
ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. Engine speed signal TM-53
4. CAN communication line LAN-4
5. Input speed sensorInput speed sensorTM-48
6. Output speed sensor and vehicle speed signalTM-50,
TM-76
7. Fluid level and state TM-148
8. Control valve with TCMTM-172
OFF vehicle9. Front brake (brake band)
TM-19210. Input clutchTM-227
11. High and low reverse clutchTM-237
12. Direct clutchTM-239
8Shock is too large for
lock-up. ON vehicle1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. Engine speed signal TM-53
4. CAN communication line LAN-4
5. Input speed sensorTM-48
6. Output speed sensor and vehicle speed signalTM-50,
TM-76
7. Torque converter clutch solenoid valve TM-65
8. Fluid level and stateTM-148
9. Control valve with TCMTM-172
OFF vehicle 10. Torque converter TM-172
9Shock is too large dur-
ing engine brake. ON vehicle
1. Accelerator pedal position sensor
TM-71
2. Control cable adjustmentTM-164
3. CAN communication line LAN-4
4. Fluid level and stateTM-148
5. Control valve with TCMTM-172
OFF vehicle6. Front brake (brake band)
TM-1727. Input clutchTM-172
8. High and low reverse clutchTM-172
9. Direct clutchTM-172
No. ItemsSymptom Condition Diagnostic ItemReference
page
Revision: April 20092010 QX56

TM-124
< SYMPTOM DIAGNOSIS >
SYSTEM SYMPTOM
10No Up
Shift Gear does not change
from D →
D2. ON vehicle 1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Direct clutch solenoid valve TM-86
4. Line pressure testTM-157
5. CAN communication line LAN-4
6. Control valve with TCMTM-172
OFF vehicle 7. Direct clutch TM-172
11Gear does not change
from D → D
3. ON vehicle 1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. High and low reverse clutch solenoid valve TM-88
4. Line pressure testTM-157
5. CAN communication line LAN-4
6. Control valve with TCMTM-172
OFF vehicle 7. High and low reverse clutch TM-172
12Gear does not change
from D →
D4. ON vehicle 1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Input clutch solenoid valve TM-82
4. Front brake solenoid valveTM-84
5. Line pressure testTM-157
6. CAN communication line LAN-4
7. Control valve with TCMTM-172
OFF vehicle 8. Input clutch TM-172
13Gear does not change
from D →
D5. ON vehicle 1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Front brake solenoid valve TM-84
4. Direct clutch solenoid valveTM-86
5. Input speed sensorTM-48
6. Line pressure testTM-157
7. CAN communication line LAN-4
8. Control valve with TCMTM-172
OFF vehicle9. Front brake (brake band)
TM-17210. Input clutchTM-172
No. ItemsSymptom Condition Diagnostic ItemReference
page
Revision: April 20092010 QX56

SYSTEM SYMPTOMTM-125
< SYMPTOM DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
14
No Down
Shift In “D” or "4" range,
does not downshift to
4GR.
ON vehicle1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Front brake solenoid valve TM-84
4. Direct clutch solenoid valveTM-86
5. CAN communication line LAN-4
6. Line pressure testTM-157
7. Control valve with TCMTM-172
OFF vehicle8. Front brake (brake band)
TM-1729. Input clutchTM-172
15In “D” or "3" range,
does not downshift to
3GR. ON vehicle1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Input clutch solenoid valve TM-82
4. Front brake solenoid valveTM-84
5. CAN communication line LAN-4
6. Line pressure testTM-157
7. Control valve with TCMTM-172
OFF vehicle 8. Input clutch TM-172
16In “D” or "2" range,
does not downshift to
2GR.
. ON vehicle1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. High and low reverse clutch solenoid valve TM-88
4. CAN communication line LAN-4
5. Line pressure testTM-157
6. Control valve with TCMTM-172
OFF vehicle 7. High and low reverse clutch TM-172
17In “D” or "1" range,
does not downshift to
1GR. ON vehicle1. Fluid level and state
TM-148
2. Output speed sensor and vehicle speed signal TM-50,
TM-76
3. Direct clutch solenoid valve TM-86
4. CAN communication line LAN-4
5. Line pressure testTM-157
6. Control valve with TCMTM-172
OFF vehicle 7. Direct clutch TM-172
No. ItemsSymptom Condition Diagnostic ItemReference
page
Revision: April 20092010 QX56