Cruise INFINITI QX56 2004 Factory User Guide

ACS-36
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMSPFP:00000
Diagnostic Trouble Code (DTC) ChartEKS007X2
×:Applicable
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Vehicle-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake
assist
(with pre-
view
function)
11 CONTROL UNIT××××

ICC unit internal malfunctionACS-37
12 VDC CONTROL UNIT××××

VDC malfunction

Brake booster signal harness is
open or shortedACS-37
20 CAN COMM CIRCUIT××××
ICC unit detected CAN communi-
cation malfunctionACS-38
31 POWER SUPPLY CIR1××××
ICC unit power supply voltage is
excessively low (less than 8V)ACS-38
34 POWER SUPPLY CIR2××××
ICC unit power supply voltage is
excessively high.ACS-38
41 VHCL SPEED SE CIRC××××

Wheel sensor malfunction

ABS actuator and electric unit
(control unit) malfunction

AT vehicle speed sensor mal-
function

TCM malfunctionACS-39
43 VDC/TCS/ABS CIRC××××
VDC/TCS/ABS system malfunc-
tionACS-39
45 BRAKE SW/ STOP L SW××××

ICC brake switch or stop lamp
switch harness is open or shorted

ICC brake switch or stop lamp
switch is stuck to OFF

ICC brake switch or stop lamp
switch is stuck to ONACS-40
46 OPERATION SW CIRC×××

ICC steering switch harness or
spiral cable is open or shorted

ICC steering switch malfunctionACS-41
74 LASER BEAM OFF CNTR×× ×
Laser beam of ICC sensor is off
the aiming pointACS-42
90 STOP LAMP RLY FIX×× ×
Normally open terminal of stop
lamp relay is stuckACS-43
92 ECM CIRCUIT××××

ECM malfunction

Accelerator pedal position sensor
malfunction

ICC unit malfunctionACS-47
96 NP RANGE×××

Park/neutral position switch har-
ness is open or shorted

Park/neutral position switch mal-
function

TCM malfunctionACS-48
97 AT CIRCUIT××
TCM malfunctionACS-48

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-37
[ICC]
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DTC 11 CONTROL UNITEKS007X3
1. DIAGNOSTIC CHECK
1. Are any items other than “DTC 11 CONTROL UNIT” indicated on self-diagnosis display?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> Replace ICC unit. Refer to ACS-59, "
ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
DTC 12 VDC CONTROL UNITEKS008DH
1. DIAGNOSIS CHECK
With CONSULT-II

Perform self-diagnosis of ABS actuator and electric unit (control unit). Is malfunction indicated?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then per-
form self-diagnosis of ICC system again.
NO >> GO TO 2.
2. CHECK CONNECTOR ICC UNIT AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
1. Turn ignition switch OFF.
2. Disconnect connectors of ICC unit and ABS actuator and electric unit (control unit), and connect them
securely again. Then erase DTC. Then, perform self-diagnosis of ICC system again.
OK or NG
OK >> Poor connector connection. Check connector housing for disconnected, loose, bent and col-
lapsed terminals. If any malfunction is detected, repair applicable part. After repair, erase DTC
and perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 3.
98 GEAR POSITION××

TCM malfunction

AT turbine revolution sensor mal-
function

AT vehicle speed sensor mal-
functionACS-49
102 LASER STAIN×× ×
ICC sensor body window has
contaminationACS-49
103 LASER SENSOR FAIL×× ×
ICC sensor internal malfunctionACS-50
104 LASER AIMING INCMP×× ×
Laser beam aiming of ICC sensor
is not adjustedACS-50
107 LASER COMM FAIL×× ×

CAN data received by ICC sen-
sor is strange (from ICC unit,
combination meter or ECM)ACS-51
109 LASER HIGH TEMP×× ×
Temperature around ICC sensor
is excessively highACS-51
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Vehicle-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake
assist
(with pre-
view
function)

ACS-52
[ICC]
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
TROUBLE DIAGNOSIS FOR SYMPTOMSPFP:00007
Symptom ChartEKS007XR
Symptoms Reference page
OperationON/OFF switch does not switch ON.Symptom 1
ACS-53
ON/OFF switch does not switch OFF.Symptom 1
ACS-53
Cruise does not function for setting (powering functions).Symptom 2
ACS-53
CANCEL switch does not function.Symptom 3
ACS-54
RESUME does not function.Symptom 3
ACS-54
The set speed does not increase.Symptom 3
ACS-54
The set distance to the vehicle ahead cannot be changed.Symptom 3
ACS-54
The ICC is not cancelled when the gear is in other than D.Symptom 4
ACS-55
Display/ChimeThe ICC system display does not appear.Check combination meter.
Refer to DI-17, "
How to Pro-
ceed With Trouble Diagnosis"
Chime does not function.Symptom 5
ACS-55
Control Driving force is hunting.Symptom 6
ACS-56
Function to detect the vehicle
aheadThe system frequently cannot detect the vehicle ahead.Symptom 7
ACS-56
The distance to detect the vehicle ahead is short.Symptom 7
ACS-56
The system misidentifies a vehicle even though there is no
vehicle ahead.

Refer to ACS-12, "LASER
BEAM AIMING ADJUST-
MENT"

Refer to ACS-9, "ICC Sys-
tem Running Test"
The system misidentifies a vehicle in the next lane.

Refer to ACS-12, "LASER
BEAM AIMING ADJUST-
MENT"

Refer to ACS-9, "ICC Sys-
tem Running Test"
The system does not detect a vehicle at all.Symptom 8
ACS-56

AT-1
AUTOMATIC TRANSMISSION
C TRANSMISSION/TRANSAXLE
CONTENTS
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SECTION AT
A
B
AT
Revision: August 20072004 QX56 INDEX FOR DTC ........................................................ 5
Alphabetical Index .................................................... 5
DTC No. Index ......................................................... 6
PRECAUTIONS .......................................................... 7
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 7
Precautions for On Board Diagnostic (OBD) System
of A/T and Engine .................................................... 7
Precautions .............................................................. 8
Service Notice or Precautions .................................. 9
Wiring Diagrams and Trouble Diagnosis .................. 9
PREPARATION ......................................................... 10
Special Service Tools ............................................. 10
Commercial Service Tools ...................................... 12
A/T FLUID ................................................................. 13
Changing A/T Fluid ................................................ 13
Checking A/T Fluid ................................................. 13
A/T Fluid Cooler Cleaning ...................................... 15
A/T CONTROL SYSTEM .......................................... 18
Cross-Sectional View (2WD models) ..................... 18
Cross-Sectional View (4WD models) ..................... 19
Shift Mechanism ..................................................... 20
TCM Function ......................................................... 31
CAN Communication .............................................. 32
Input/Output Signal of TCM .................................... 32
Line Pressure Control ............................................ 33
Shift Control ........................................................... 34
Lock-up Control ...................................................... 35
Engine Brake Control ............................................. 37
Control Valve .......................................................... 37
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 39
Introduction ............................................................ 39
OBD-II Function for A/T System ............................. 39
One or Two Trip Detection Logic of OBD-II ............ 39
OBD-II Diagnostic Trouble Code (DTC) ................. 39
Malfunction Indicator Lamp (MIL) ........................... 42
TROUBLE DIAGNOSIS ............................................ 43
DTC Inspection Priority Chart ................................ 43
Fail-Safe ................................................................. 43How To Perform Trouble Diagnosis For Quick and
Accurate Repair ...................................................... 45
A/T Electrical Parts Location .................................. 50
Circuit Diagram ....................................................... 51
Wiring Diagram — AT — ........................................ 52
Inspections Before Trouble Diagnosis .................... 58
Check Before Engine is Started .............................. 62
Check at Idle ........................................................... 62
Cruise Test - Part 1 ................................................. 63
Cruise Test - Part 2 ................................................. 65
Cruise Test - Part 3 ................................................. 66
Vehicle Speed When Shifting Gears ...................... 67
Vehicle Speed When Performing and Releasing
Complete Lock-up .................................................. 67
Vehicle Speed When Performing and Releasing
Slip Lock-up ............................................................ 67
Symptom Chart ....................................................... 68
TCM Input/Output Signal Reference Values ........... 90
CONSULT-II Function (A/T) .................................... 91
DTC U1000 CAN COMMUNICATION LINE ............103
Description ............................................................103
On Board Diagnosis Logic ....................................103
Possible Cause .....................................................103
DTC Confirmation Procedure ...............................103
Diagnostic Procedure ...........................................104
DTC P0615 START SIGNAL CIRCUIT ...................105
Description ............................................................105
CONSULT-II Reference Value ..............................105
On Board Diagnosis Logic ....................................105
Possible Cause .....................................................105
DTC Confirmation Procedure ...............................105
Diagnostic Procedure ...........................................106
DTC P0700 TCM .....................................................108
Description ............................................................108
On Board Diagnosis Logic ....................................108
Possible Cause .....................................................108
DTC Confirmation Procedure ...............................108
Diagnostic Procedure ...........................................108
DTC P0705 PARK/NEUTRAL POSITION SWITCH .109
Description ............................................................109

TROUBLE DIAGNOSIS
AT-61
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Judgement of Line Pressure Test
ROAD TEST
Description

The road test inspects overall performance of the A/T and analyzes possible malfunction causes.

The road test is carried out in the following three stages.
1. Check before engine is started. Refer to AT - 6 2
.
2. Check at idle. Refer to AT- 6 2
.
3. Cruise test

Inspect all the items from Part 1 to Part 3. Refer to AT- 6 3 , AT- 6 5 , AT- 6 6 .

Before beginning the road test, check the test procedure and inspection items.

Test all inspection items until the symptom is uncovered. Diagnose NG items when all road tests are com-
plete.
Judgement Possible cause
Idle speedLow for all positions
(P, R, N, D)Possible causes include malfunctions in the pressure supply system and low oil pump output.
For example

Oil pump wear

Pressure regulator valve or plug sticking or spring fatigue

Oil strainer
oil pump
pressure regulator valve passage oil leak

Engine idle speed too low
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
HighPossible causes include a sensor malfunction or malfunction in the line pressure adjustment func-
tion.
For example

Accelerator pedal position signal malfunction

ATF temperature sensor malfunction

Line pressure solenoid malfunction (sticking in “OFF” state, filter clog, cut line)

Pressure regulator valve or plug sticking
Stall speedOil pressure does
not rise higher than
the oil pressure for
idle.Possible causes include a sensor malfunction or malfunction in the pressure adjustment function.
For example

Accelerator pedal position signal malfunction

TCM breakdown

Line pressure solenoid malfunction (shorting, sticking in“ ON” state)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
The pressure rises,
but does not enter
the standard posi-
tion.Possible causes include malfunctions in the pressure supply system and malfunction in the pres-
sure adjustment function.
For example

Accelerator pedal position signal malfunction

Line pressure solenoid malfunction (sticking, filter clog)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.

TROUBLE DIAGNOSIS
AT-63
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4. CHECK “N” POSITION FUNCTIONS
1. Start the engine.
2. Move selector lever to “N” position.
3. Release the parking brake.
Does vehicle move forward or backward?
YES >> Enter a check mark at “Vehicle moves in “N” position” on the diagnostics worksheet, then continue
the road test.
NO >> GO TO 5.
5. CHECK SHIFT SHOCK
1. Engage the brake.
2. Move selector lever to “D” position.
When the transmission is shifted from
“N” to “D”, is there an excessive shock?
YES >> Enter a check mark at “Large shock when shifted from N to D” on the diagnostics worksheet, then
continue the road test.
NO >> GO TO 6.
6. CHECK “R” POSITION FUNCTIONS
1. Engage the brake.
2. Move selector lever to “R” position.
3. Disengage the brake for 4 to 5 seconds.
Does the vehicle creep backward?
YES >> GO TO 7.
NO >> Enter a check mark at “Vehicle does not creep backward in R position” on the diagnostics work-
sheet, then continue the road test.
7. CHECK “D” POSITION FUNCTIONS
Inspect whether the vehicle moves forward when the transmission is put into the “D” position.
Does the vehicle creep forward in the
“D” positions?
YES >> Go to AT- 6 3 , "Cruise Test - Part 1" , AT- 6 5 , "Cruise Test - Part 2" , and AT- 6 6 , "Cruise Test - Part
3" .
NO >> Enter a check mark at “Vehicle does not move forward in D positions” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1UCS002D0
1. CHECK STARTING OUT FROM D1
1. Drive the vehicle for about 10 minutes to warm up the engine oil and ATF.
Appropriate temperature for the ATF: 50 - 80°C (122 - 176°F)
2. Park the vehicle on a level surface.
3. Move selector lever to “P” position.
4. Start the engine.
5. Move selector lever to “D” position.
6. Press the accelerator pedal about half way down to accelerate the vehicle.
With CONSULT-II
Read off the gear positions.
Starts from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle cannot be started from D1” on the diagnostics worksheet, then
continue the road test.

TROUBLE DIAGNOSIS
AT-65
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6. CHECK LOCK-UP
When releasing accelerator pedal from D5, check lock-up from D5 to L/U.

Refer to AT- 6 7 , "Vehicle Speed When Shifting Gears" .
With CONSULT-II
Select “TCC SOLENOID 0.00A” with the “MAIN SIGNAL” mode for A/T.
Does it lock-up?
YES >> GO TO 7.
NO >> Enter a check mark at “A/T does not perform lock-up” on the diagnostics worksheet, then continue
the road test.
7. CHECK LOCK-UP HOLD
Does it maintain lock-up status?
YES >> GO TO 8.
NO >> Enter a check mark at “A/T hold does not lock-up condition” on the diagnostics worksheet, then
continue the road test.
8. CHECK LOCK-UP RELEASE
Check lock-up cancellation by depressing brake pedal lightly to decelerate.
With CONSULT-II
Select “TCC SOLENOID 0.00A” with the “MAIN SIGNAL” mode for A/T.
Does lock-up cancel?
YES >> GO TO 9.
NO >> Enter a check mark at “Lock-up is not released” on the diagnostics worksheet, then continue the
road test.
9. CHECK SHIFT-DOWN D5 → D4
Decelerate by pressing lightly on the brake pedal.
With CONSULT-II
Read the gear position and engine speed.
When the A/T shift-down D5
→ D4, does the engine speed drop smoothly back to idle?
YES >> 1. Stop the vehicle.
2. Go to Cruise test - Part 2 (Refer to AT- 6 5
).
NO >> Enter a check mark at “A/T does not shift-down” on the diagnostics worksheet, then continue the
road test. Go to Cruise test - Part 2 (Refer to AT- 6 5
).
Cruise Test - Part 2UCS002D1
1. CHECK STARTING FROM D1
1. Move selector lever the “D” position.
2. Accelerate at half throttle.
With CONSULT-II
Read the gear position.
Does it start from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle cannot be started from D1” on the diagnostics worksheet, then
continue the road test.

AT-66
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
2. CHECK SHIFT-UP D1 → D2
Press the accelerator pedal down all the way and inspect whether or not the transmission shifts up (D1 → D2)
at the correct speed.

Refer to AT-67, "Vehicle Speed When Shifting Gears" .
With CONSULT-II
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D1
→ D2 at the correct speed?
YES >> GO TO 3.
NO >> Enter a check mark at “Vehicle does not shift D1 → D2” on the diagnostics worksheet, then con-
tinue the road test.
3. CHECK SHIFT-UP D2 → D3
Press the accelerator pedal down all the way and inspect whether or not the transmission shifts up (D2 → D3)
at the correct speed.

Refer to AT-67, "Vehicle Speed When Shifting Gears" .
With CONSULT-II
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D2
→ D3 at the correct speed?
YES >> GO TO 4.
NO >> Enter a check mark at “Vehicle does not shift D2 → D3” on the diagnostics worksheet, then con-
tinue the road test.
4. CHECK SHIFT-UP D3 → D4 AND ENGINE BRAKE
When the transmission changes speed D3 → D4, return the accelerator pedal.
Does the A/T shift-up D3
→ D4 and apply the engine brake?
YES >> 1. Stop the vehicle.
2. See AT-66, "
Cruise Test - Part 3" .
NO >> Enter a check mark at “Vehicle does not shift D3 → D4” on the diagnostics worksheet, then con-
tinue the road test.
Cruise Test - Part 3UCS002D2
1. CHECK SHIFT-DOWN
During D
5 driving, move gear selector from D → 4 → 3 → 2 → 1.
With CONSULT-II
Read the gear position.
Is downshifting correctly performed?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle does not shift” at the corresponding position (5th → 4th, 4th → 3rd,
3rd → 2nd, 2nd → 1st) on the diagnostics worksheet, then continue the road test.
2. CHECK ENGINE BRAKE
Does engine braking effectively reduce speed in 1
1 position?
YES >> 1. Stop the vehicle.
2. Carry out the self-diagnostics. Refer to AT-93, "
SELF-DIAGNOSTIC RESULT MODE" .
NO >> Enter a check mark at “Vehicle does not decelerate by engine brake” on the diagnostics work-
sheet, then continue trouble diagnosis.

AT-98
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
ATF PRES SW 5 (ON-OFF display) X X X (for D/C solenoid)
ATF PRES SW 6 (ON-OFF display) X X X (for HLR/C solenoid)
PNP SW 1 (ON-OFF display) X — X
PNP SW 2 (ON-OFF display) X — X
PNP SW 3 (ON-OFF display) X — X
PNP SW 4 (ON-OFF display) X — X
SLCT LVR POSI — X XSelector lever position is recognized by the
TCM.
For fail-safe operation, the specific value used
for control is displayed.
1 POSITION SW (ON-OFF display) X — X 1st position switch
OD CONT SW (ON-OFF display) X — X 4th position switch
POWERSHIFT SW (ON-OFF display) X — X
Not mounted but displayed. HOLD SW (ON-OFF display) X — X
MANU MODE SW (ON-OFF display) X — X
NON M-MODE SW (ON-OFF display) X — X
UP SW LEVER (ON-OFF display) X — X
DOWN SW LEVER (ON-OFF display) X — X
SFT UP ST SW (ON-OFF display) — — X
SFT DWN ST SW (ON-OFF display) — — X
ASCD-OD CUT (ON-OFF display) — — X
ASCD-CRUISE (ON-OFF display) — — X
ABS SIGNAL (ON-OFF display) — — X
ACC OD CUT (ON-OFF display) — — X
ICC (Intelligent cruise control)
ACC SIGNAL (ON-OFF display) — — X
TCS GR/P KEEP (ON-OFF display) — — X
TCS SIGNAL 2 (ON-OFF display) — — X
TCS SIGNAL 1 (ON-OFF display) — — X
TCC SOLENOID (A) — X X
LINE PRES SOL (A) — X X
I/C SOLENOID (A) — X X
FR/B SOLENOID (A) — X X
D/C SOLENOID (A) — X X
HLR/C SOL (A) — X X
ON OFF SOL (ON-OFF display) — — X LC/B solenoid
TCC SOL MON (A) — — X
L/P SOL MON (A) — — X
I/C SOL MON (A) — — X
FR/B SOL MON (A) — — X
D/C SOL MON (A) — — X
HLR/C SOL MON (A) — — X
ONOFF SOL MON (ON-OFF display) — — X LC/B solenoidMonitored item (Unit)Monitor Item Selection
Remarks ECU
INPUT
SIGNALSMAIN SIG-
NALSSELEC-
TION
FROM
MENU

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-203
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9. DETECT MALFUNCTIONING ITEM

Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.43).
OK or NG
OK >> GO TO 10.
NG >> Repair or replace damaged parts.
10. CHECK SYMPTOM
Check again. Refer to AT- 6 2 , "
Check at Idle" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 11.
11 . PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Val-
ues" .
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.
12. DETECT MALFUNCTIONING ITEM

Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.43).
OK or NG
OK >> GO TO 10.
NG >> Repair or replace damaged parts.
Vehicle Cannot Be Started From D1UCS002IP
SYMPTOM:
Vehicle cannot be started from D1 on cruise test - Part 1.
DIAGNOSTIC PROCEDURE
1. CONFIRM THE SYMPTOM
Check if vehicle creeps in “R” position.
OK or NG
OK >> GO TO 2.
NG >> Refer to AT-198, "
Vehicle Does Not Creep Backward In “R” Position" .
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 3 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is any malfunction detected by self-diagnostic results?
YES >> Check the malfunctioning system.
NO >> GO TO 3.