2004 INFINITI QX56 Meter

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-37
[ICC]
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ACS
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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-50
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
2. VISUAL INSPECTION (2)

Check ICC sensor body window for cracks.
OK or NG
OK >> GO TO 3.
NG >>

Replace ICC sensor and adjust laser beam. Refer to ACS-12, "LASER BEAM AIMING
ADJUSTMENT" .

After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
3. ASK CUSTOMER FOR DRIVING CONDITIONS
1. Is there any trace of contamination or foreign material on ICC sensor?
2. Is there any possibility that vehicle was driven in snow or ICC sensor was frosted?
3. Is there any possibility that ICC sensor was fogged temporarily? (Front window glass may have also been
fogged.)
Ye s o r N o
Yes >> Explain system operation and parameters to customer. System may be operating normally.
No >>

Replace ICC sensor and adjust laser beam aiming. Refer to ACS-59, "ICC Sensor" .

After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
DTC 103 LASER SENSOR FAILEKS007XL
1. DIAGNOSTIC CHECK

Are “DTC 11 CONTROL UNIT” or “DTC 20 CAN COMM CIRCUIT” item indicated in self-diagnosis display
item?
YES or NO
YES >> GO TO APPLICABLE ITEM INSPECTION. Refer to ACS-37, "DTC 11 CONTROL UNIT" , and
ACS-38, "
DTC 20 CAN COMM CIRCUIT" .
NO >>

Replace ICC sensor and adjust laser beam aiming. Refer to ACS-59, "ICC Sensor" .

After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
DTC 104 LASER AIMING INCMPEKS007XM
1. DIAGNOSTIC CHECK
1. Adjust laser beam aiming. Refer to ACS-12, "
LASER BEAM AIMING ADJUSTMENT" . Erase DTC and
perform ICC system running test.
2. After that, perform self-diagnosis of ICC system. Is “DTC 104 LASER AIMING INCMP” indicated?
CAUTION:
Ensure that laser beam aiming apparatus is set up accurately.
YES or NO
YES >>
Replace ICC sensor and adjust laser beam aiming. Refer to ACS-59, "ICC Sensor" .

After that, erase DTC and perform ICC system running test. Then perform self-diagnosis of ICC
system again.
NO >> Inspection end.

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

TROUBLE DIAGNOSIS FOR SYMPTOMS
ACS-53
[ICC]
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Symptom 1: ON/OFF Switch Does Not Switch ON*1 , ON/OFF Switch Does Not
Switch OFF
*2EKS007XS
NOTE:

*1: The ICC system display in the combination meter does not illuminate.

*2: The ICC system display in the combination meter remains powered.
1. CHECK ON/OFF SWITCH
With CONSULT-II

With data monitor, check that ON/OFF switch operates normally.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. CHECK ICC UNIT CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect ICC unit harness connectors.
3. Check connector housing for disconnected, loose, bent, and collapsed terminals.
OK or NG
OK >> GO TO 3.
NG >>

Poor connector connection.

Repair ICC unit connector. After repair, erase DTC and perform ICC system running test. Then
perform self-diagnosis of ICC system again.
3. DIAGNOSIS CHECK
With CONSULT-II

Perform self-diagnosis with CONSULT-II. Is “CAN COMM CIRCUIT” indicated?
YES or NO
YES >> Refer to ACS-38, "DTC 20 CAN COMM CIRCUIT" .
NO >> Refer to ACS-41, "
DTC 46 OPERATION SW CIRC" .
Symptom 2: The ICC System Cannot Be Set (ON/OFF Switch Turns On/Off)EKS007XT
The ICC cannot be set in the following cases.

When the vehicle speed is not in range of approx. 25 MPH (40 km/h) to 89 MPH (144 km/h).

When the A/T selector lever is in gears other than "D".

While the brake is in operation.

When the windshield wipers are operating.
1. CHECK CAUSE OF AUTOMATIC CANCELLATION
With CONSULT-II
1. With “CAUSE OF AUTO-CANCEL” in work support, check if any cause of cancellation exists.
OK or NG
OK >>
Cancel with appropriate cause.

For causes A, B, or C, go to specified diagnosis.
A: “OPE SW VOLT CIRC” : Refer to ACS-41, "
DTC 46 OPERATION SW CIRC" .
B: “VHCL SPD UNMATCH” : Refer to ACS-39, "
DTC 41 VHCL SPEED SE CIRC" .
C: “IGN LOW VOLT” : Refer to ACS-38, "
DTC 31 POWER SUPPLY CIR 1, DTC 34
POWER SUPPLY CIR 2" .
NG >> GO TO 2.

ACS-56
[ICC]
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CAN COMMUNICATION INSPECTION
With CONSULT-II
1. With CONSULT-II self-diagnosis, check “CAN COMM CIRCUIT”.
OK or NG
OK >> Refer to ACS-38, "DTC 20 CAN COMM CIRCUIT" .
NG >> Replace combination meter and erase DTC. Refer to DI-25, "
Removal and Installation of Combi-
nation Meter" . Perform ICC system running test, and then perform self-diagnosis of ICC system
again.
Symptom 6: Driving Force Is HuntingEKS007XX
1. CHECK ECM
1. Perform self-diagnosis of ECM.
OK or NG
OK >> Refer to ACS-56, "Symptom 7: The ICC System Frequently Cannot Detect the Vehicle Ahead/The
Detection Zone is Short" .
NG >> After repairing applicable parts, erase DTC. Perform ICC system running test, and then perform
self-diagnosis of ICC system again.
Symptom 7: The ICC System Frequently Cannot Detect the Vehicle Ahead/The
Detection Zone is Short
EKS007XY
The detection function may become unstable in the following cases:

When the reflector of the vehicle ahead is small or not clean enough to reflect the laser.

When driving a road with extremely sharp corners.

When the laser cannot detect the reflector of the vehicle ahead as the vehicle ahead is passing a hill or
passing the peak.
1. VISUAL CHECK
1. Check ICC sensor body window for contamination and foreign materials.
OK or NG
OK >> If any contamination or foreign materials are found, remove them. Then perform ICC system run-
ning test.
NG >> GO TO 2.
2. CHECK FUNCTION
1. After performing laser beam aiming adjustment, perform ICC system running test. Check that preceding
vehicle detection performance has been improved.
OK or NG
OK >> Inspection End.
NG >>

Replace ICC sensor and perform laser beam aiming adjustment. Refer to ACS-59, "ICC Sen-
sor" .

After performing above, perform ICC system running test, and then perform self-diagnosis of
ICC system again.
Symptom 8: The System Does Not Detect the Vehicle Ahead at AllEKS007XZ
1. VISUAL CHECK
1. With ignition switch turned ON (engine not started), check that all indicator lamps in ICC system display
are continuously lit. (Check for a missing segment in preceding vehicle detection display.)
OK or NG
OK >> GO TO 2.
NG >> Check combination meter. Refer to DI-17, "
How to Proceed With Trouble Diagnosis" .

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartUCS002C R
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 perform the trouble diagnosis for DTC U1000. Refer to
AT-1 03
.
Fail-SafeUCS002CS
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is a an error in
a main electronic control input/output signal circuit. In fail-safe mode the transmission is fixed in 2nd or 4th
(depending on the breakdown position), so the customer should feel “slipping” or “poor acceleration”. When
fail-safe mode is triggered, when the ignition switch is switched “ON”, the AT CHECK indicator lamp flashes for
about 8 seconds.
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. Also, the AT CHECK indicator lamp flashes for about 8 seconds once, then is cleared.
Therefore, the customer's vehicle has returned to normal, so handle according to the “diagnostics flow” (Refer
to AT-46, "
WORK FLOW" ).
FAI L-S AFE FUN CT ION
If any malfunction occurs in a sensor or solenoid, this function controls the A/T to mark driving possible.
Vehicle Speed Sensor

Signals are input from two systems - from vehicle speed sensor A/T (revolution sensor) installed on the
transmission and from combination meter so normal driving is possible even if there is a malfunction in
one of the systems. And if vehicle speed sensor A/T (revolution sensor) has unusual cases, 5th gear is
prohibited.
Accelerator Pedal Position Sensor

If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM accord-
ing to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow
systems, 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 accord-
ing to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow
systems, 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.
PNP Switch

In the unlikely event that a malfunction signal enters the 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” range to make driving possible.
Starter Relay

The starter relay is switched “OFF”. (Starter starting is disabled.)
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
CONSULT-II Function (A/T)UCS002D8
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II REFERENCE VALUE
NOTICE:
1. The CONSULT-II electrically displays shift timing and lock-up timing (that is, operation timing of each sole-
noid).
Check for time difference between actual shift timing and the CONSULT-II display. If the difference is
noticeable, mechanical parts (except solenoids, sensors, etc.) may be malfunctioning. Check mechanical
parts using applicable diagnostic procedures.
2. Shift schedule (which implies gear position) displayed on CONSULT-II and that indicated in Service Man-
ual may differ slightly. This occurs because of the following reasons:
–Actual shift schedule has more or less tolerance or allowance,
–Shift schedule indicated in Service Manual refers to the point where shifts start, and
–Gear position displayed on CONSULT-II indicates the point where shifts are completed.
3. Display of solenoid valves on CONSULT-II changes at the start of shifting, while gear position is displayed
upon completion of shifting (which is computed by TCM).
TCM diagnostic mode Description
WORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the TCM for setting the status
suitable for required operation, input/output signals are received from the TCM and received data is
displayed.
SELF-DIAG RESULTS Displays TCM self-diagnosis results.
DATA MONITOR Displays TCM input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
FUNCTION TESTConducted by CONSULT-II instead of a technician to determine whether each system is “OK” or
“NG”.
ECU PART NUMBER TCM part number can be read.
Item name Condition Display value
AT F T E M P S E 1
0°C (32° F) - 20°C (68°F) - 80°C (176°F)3.2 - 2.5 - 0.8 V
AT F T E M P S E 23.2 - 2.4 - 0.65 V
TCC SOLENOIDWhen perform slip lock-up 0.2 - 0.4 A
When perform lock-up 0.4 - 0.6 A
SLCT LVR POSISelector lever in “N”,“P” position. N/P
Selector lever in “R” position. R
Selector lever in “D” position. D
Selector lever in “4” position. 4
Selector lever in “3” position. 3
Selector lever in “2” position. 2
Selector lever in “1” position. 1
VHCL/S SE·A/T During driving Approximately matches the
speedometer reading.
ENGINE SPEED Engine running Closely matches the tachometer
reading.
LINE PRES SOL During driving 0.2 - 0.6 A
TURBINE REV During driving (lock-up ON) Approximately matches the
engine speed.
VHCL/S SE·MTR During driving Approximately matches the
speedometer reading.

AT-112
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)
Revision: August 20072004 QX56
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)PFP:32702
DescriptionUCS002DV
The revolution sensor detects the revolution of the idler gear parking pawl lock gear and emits a pulse signal.
The pulse signal is sent to the TCM which converts it into vehicle speed.
CONSULT-II Reference ValueUCS002DW
On Board Diagnosis LogicUCS002DX

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “VEH SPD SEN/CIR AT” with CONSULT-II or P0720 without CONSULT-II is
detected under the following conditions.
–When TCM does not receive the proper voltage signal from the sensor.
–After ignition switch is turned “ON”, irregular signal input from vehicle speed sensor MTR before the vehi-
cle starts moving.
Possible CauseUCS002DY

Harness or connectors
(The sensor circuit is open or shorted.)

Revolution sensor

Vehicle speed sensor MTR
DTC Confirmation ProcedureUCS002DZ
CAUTION:

Always drive vehicle at a safe speed.

Be careful not to rev engine into the red zone on the tachometer.
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-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Drive vehicle and check for an increase of “VHCL/S SE·A/T”
value in response to “VHCL/S SE·MTR” value.
If the check result is NG, go to AT-113, "
Diagnostic Procedure" .
If the check result is OK, go to following step.
4. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
5. Start engine and maintain the following conditions for at least 5
consecutive seconds.
VHCL SPEED SE: 30 km/h (19 MPH) or more
THRTL POS SEN: More than 1.0/8
Selector lever: “D” position
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
If the check result is NG, go to AT-113, "
Diagnostic Procedure" .
If the check result is OK, go to following step.
6. Maintain the following conditions for at least 5 consecutive seconds.
ENGINE SPEED: 3,500 rpm or more
THRTL POS SEN: More than 1.0/8
Selector lever: “D” position
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
If the check result is NG, go to AT-113, "
Diagnostic Procedure" .
Item name Condition Display value (km/h)
VHCL/S SE·A/T During driving Approximately matches the speedometer reading.
BCIA0030E