2007 INFINITI QX56 Cruise

AT-194
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYMPTOMS
5.CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-210, "
Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.14).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.14).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
A/T Does Not Shift: 4th gear → 3rd gearINFOID:0000000003532465
SYMPTOM:
When shifted from 44 to 33 position, does not downshift from 4th to 3rd gears.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis. Refer to AT-83, "
CONSULT-II Function (A/T)".
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 1, ATF pressure switch 3?
YES >> Check the malfunctioning system. Refer to AT- 9 9, AT-150' AT-152.
NO >> GO TO 2.
2.CHECK A/T FLUID LEVEL
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-195
< SERVICE INFORMATION >
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Check the A/T fluid level. Refer to AT-13, "Checking Automatic
Transmission Fluid (ATF)".
OK or NG
OK >> GO TO 3.
NG >> Refill ATF.
3.CHECK CONTROL CABLE
Check the control cable.
• Refer to AT-208, "
Checking of A/T Position".
OK or NG
OK >> GO TO 4.
NG >> Adjust control cable. Refer to AT-208, "
Adjustment of A/
T Position".
4.CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-210, "
Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 5.
NG >> GO TO 8.
5.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.15).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
SAT638A
LCIA0345E
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-197
< SERVICE INFORMATION >
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2. Check A/T fluid condition. Refer to AT-51, "Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 5.
NG >> GO TO 8.
5.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.16).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
8.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.16).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
A/T Does Not Shift: 2nd gear → 1st gearINFOID:0000000003532467
SYMPTOM:
When shifted from 22 to 11 position, does not downshift from 2nd to 1st gears.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis. Refer to AT-83, "
CONSULT-II Function (A/T)".
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 5?
YES >> Check the malfunctioning system. Refer to AT- 9 9' AT-154.
NO >> GO TO 2.
2.CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-199
< SERVICE INFORMATION >
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1. Remove oil pan. Refer to AT-210, "Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-58, "
Cruise Test - Part 2".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
Vehicle Does Not Decelerate By Engine BrakeINFOID:0000000003532468
SYMPTOM:
No engine brake is applied when the gear is shifted from the 22 to 11.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis.
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 5?
YES >> Check the malfunctioning system. Refer to AT- 9 9' AT-154.
NO >> GO TO 2.
2.CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-201
< SERVICE INFORMATION >
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1. Remove oil pan. Refer to AT-210, "Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.53).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.53).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
SCIA5199E

EC-30
< SERVICE INFORMATION >
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System DescriptionINFOID:0000000003531591
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric throttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE indicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicator in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indicator in combination meter illuminates.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.
• CANCEL switch is pressed
• More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Selector lever is changed to N, P, R position
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
• VDC system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to the normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator Stop lamp switch Brake pedal operation
ASCD steering switch ASCD steering switch operation
Park/neutral position (PNP) switch Gear position
Wheel sensor Vehicle speed*
TCM Powertrain revolution*

EC-118
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
A/F S1 HTR (B1)
[%]• A/F sensor 1 heater control value com-
puted by ECM according to the input sig-
nals.
• The current flow to the heater becomes
larger as the value increases. A/F S1 HTR (B2)
[%]
AC PRESS SEN [V]• The signal voltage from the refrigerant
pressure sensor is displayed.
VHCL SPEED SE
[km/h] or [mph]• The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.
SET VHCL SPD
[km/h] or [mph]• The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]• Indicates [ON/OFF] condition from MAIN
switch signal.
CANCEL SW
[ON/OFF]• Indicates [ON/OFF] condition from CAN-
CEL switch signal.
RESUME/ACC SW
[ON/OFF]• Indicates [ON/OFF] condition from RE-
SUME/ACCELERATE switch signal.
SET SW
[ON/OFF]• Indicates [ON/OFF] condition from SET/
COAST switch signal.
BRAKE SW1
[ON/OFF]• Indicates [ON/OFF] condition from
ASCD brake switch signal.
BRAKE SW2
[ON/OFF]• Indicates [ON/OFF] condition of stop
lamp switch signal.
DIST SW
[ON/OFF]• Indicates [ON/OFF] condition from DIS-
TANCE switch signal.
VHCL SPD CUT
[NON/CUT]• Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed increased to exces-
sively high compared with the ASCD set
speed, and ASCD operation is cut off.
LO SPEED CUT
[NON/CUT]• Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed decreased to exces-
sively low compared with the ASCD set
speed, and ASCD operation is cut off.
AT O D M O N I T O R
[ON/OFF]• Indicates [ON/OFF] condition of A/T O/D
according to the input signal from the
TCM.
AT O D C A N C E L
[ON/OFF]• Indicates [ON/OFF] condition of A/T O/D
cancel signal sent from the TCM.
CRUISE LAMP
[ON/OFF]• Indicates [ON/OFF] condition of CRUISE
lamp determined by the ECM according
to the input signals.
SET LAMP
[ON/OFF]• Indicates [ON/OFF] condition of SET
lamp determined by the ECM according
to the input signals.
ALT DUTY [%]• Indicates the duty ratio of the power gen-
eration command value. The ratio is cal-
culated by ECM based on the battery
current sensor signal.
BAT CUR SEN [mV]• The signal voltage of battery current sen-
sor is displayed. Monitored item
[Unit]ECM IN-
PUT SIG-
NALSMAIN
SIGNALSDescription Remarks

EC-126
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
COOLING FAN• Engine: After warming up, idle the
engine
• Air conditioner switch: OFFEngine coolant temperature: 99°C
(210°F) or lessOFF
Engine coolant temperature: 100°C
(212°F) or moreHI
HO2S2 HTR (B1)
HO2S2 HTR (B2)• Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no loadON
• Engine speed: Above 3,600 rpm OFF
I/P PULLY SPD • Vehicle speed: More than 20 km/h (12 MPH)Almost the same speed as the
tachometer indication
VEHICLE SPEED• Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as the
speedometer indication
TRVL AFTER MIL • Ignition switch: ONVehicle has traveled after MIL has
turned ON.0 - 65,535 km
(0 - 40,723 mile)
A/F S1 HTR (B1)
A/F S1 HTR (B2)• Engine: After warming up, idle the engine 4 - 100%
AC PRESS SEN• Engine: Idle
• Both A/C switch and blower fan switch: ON (Compressor operates.)1.0 - 4.0V
VHCL SPEED SE• Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as the
speedometer indication
SET VHCL SPD • Engine: Running ASCD: Operating.The preset vehicle speed is dis-
played.
MAIN SW • Ignition switch: ONMAIN switch: Pressed ON
MAIN switch: Released OFF
CANCEL SW • Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW • Ignition switch: ONRESUME/ACCELERATE switch:
PressedON
RESUME/ACCELERATE switch: Re-
leasedOFF
SET SW • Ignition switch: ONSET/COAST switch: Pressed ON
SET/COAST switch: Released OFF
DIST SW • Ignition switch: ONDISTANCE switch: Pressed ON
DISTANCE switch: Released OFF
BRAKE SW1 • Ignition switch: ONBrake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
BRAKE SW2 • Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
CRUISE LAMP • Ignition switch: ONMAIN switch: Pressed at the 1st time
→ at the 2nd timeON → OFF
SET LAMP• MAIN switch: ON
• Vehicle speed: Between 40 km/h
(25 MPH) and 144 km/h (89
MPH)ASCD: Operating ON
ASCD: Not operating OFF
ALT DUTY • Engine: Idle 0 - 80%
BAT CUR SEN• Engine speed: Idle
• Battery: Fully charged*
2
• Selector lever: P or N
• Air conditioner switch: OFF
•No loadApprox. 2,600 - 3,500mV MONITOR ITEM CONDITION SPECIFICATION