turn signal INFINITI QX56 2004 Factory Workshop Manual

DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
AT-173
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Revision: August 20072004 QX56
Diagnostic ProcedureUCS002H N
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELECTION FORM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Start the engine.
4. Drive vehicle in the manual mode (“M1-1st” or “M2-2nd” gear),
and confirm the ON/OFF actuation of the “ATF PRES SW 2” and
“ON OFF SOL”.
OK or NG
OK >> GO TO 6.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Values" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 5.
3. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 7 2 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 4.
4. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT - 2 4 1 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
Item name Condition Display value
(ON-OFF dis-
play)
ON OFF SOLLow coast brake engaged. Refer to
AT- 2 1
.ON
Low coast brake disengaged. Refer
to AT-2 1
.OFF
ATF PRES
SW 2Low coast brake engaged. Refer to
AT- 2 1
.ON
Low coast brake disengaged. Refer
to AT-2 1
.OFF
SCIA4794E

CLOSED THROTTLE POSITION AND WIDE OPEN THROTTLE POSITION CIR-
CUIT
AT-187
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Revision: August 20072004 QX56
CLOSED THROTTLE POSITION AND WIDE OPEN THROTTLE POSITION CIR-
CUIT
PFP:18002
CONSULT-II Reference ValueUCS002IC
Diagnostic ProcedureUCS002ID
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT - 9 3 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 1 0 3 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK THROTTLE POSITION SIGNAL CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T” with CONSULT-II.
3. Depress accelerator pedal and read out the value of “CLSD THL
POS” and “W/O THL POS”.
OK or NG
OK >>INSPECTION END
NG >> Check the following items. If NG, repair or replace damaged parts.

Perform the self-diagnosis for “ENGINE” with CONSULT-II.

Open circuit or short to ground or short to power in harness or connectors.

Pin terminals for damage or loose connection with harness connector.
Item name Condition Display value
CLSD THL POSReleased accelerator pedal. ON
Fully depressed accelerator pedal. OFF
W/O THL POSFully depressed accelerator pedal. ON
Released accelerator pedal. OFF
Accelerator Pedal OperationMonitor Item
CLSD THL POS W/O THL POS
Released ON OFF
Fully depressed OFF ON
PCIA0070E

AT-188
BRAKE SIGNAL CIRCUIT
Revision: August 20072004 QX56
BRAKE SIGNAL CIRCUITPFP:25320
CONSULT-II Reference ValueUCS002IE
Diagnostic ProcedureUCS002IF
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT-93, "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT-103, "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK STOP LAMP SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T” with CONSULT-II.
3. Read out ON/OFF switching action of the “BRAKE SW”.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. CHECK STOP LAMP SWITCH
Check continuity between stop lamp switch harness connector termi-
nals 3 and 4.
Check stop lamp switch after adjusting brake pedal — refer to
BR-6, "
BRAKE PEDAL" .
OK or NG
OK >>INSPECTION END
NG >> Check the following items. If NG, repair or replace dam-
aged parts.

Harness for short or open between battery and stop lamp switch.

Harness for short or open between stop lamp switch and combination meter.
Item name Condition Display value
BRAKE SWDepressed brake pedal. ON
Released brake pedal. OFF
PCIA0070E
Condition Continuity
When brake pedal is depressed Yes
When brake pedal is released No
SCIA2126E

TOW MODE SWITCH
AT-189
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Revision: August 20072004 QX56
TOW MODE SWITCHPFP:25129
DescriptionUCS002IG
When tow mode switch is “ON”, tow mode switch signals are sent to TCM from combination meter by CAN
communication line.Then it`s a tow mode condition.
Diagnostic ProcedureUCS002IH
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT - 9 3 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is any malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 1 0 3 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK POWER SOURCE
1. Turn ignition switch “ON”. (Do not start engine.)
2. Check the voltage between tow mode switch connector terminal
1 and ground.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. CHECK TOW MODE SWITCH
1. Turn ignition switch “OFF”.
2. Disconnect tow mode switch connector.
3. Check continuity between tow mode switch connector M254 ter-
minals 1 and 2.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace tow mode switch.
4. DETECT MALFUNCTIONING ITEM
Check the following items. If any items are damaged, repair or replace damaged parts.

Harness for short or open between combination meter connector terminal 35 and tow mode switch con-
nector terminal 1.

Harness for short or open between tow mode switch connector terminal 2 and ground.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
ConditionTo w m o d e
switchData (Approx.)
When ignition switch is turned to “ON”ON 0V
OFF Battery voltage
SCIA5156E
Condition Continuity
To w m o d e s w i t c h “ O N ” Ye s
To w m o d e s w i t c h “ O F F ” N o
SCIA5157E

AT-222
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CHECK 4TH POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "OD CONT SW" switch moving selector lever to each
position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK A/T FLUID LEVEL
Check the A/T fluid level again. Refer to AT- 1 3 , "
Checking A/T Fluid"
.
OK or NG
OK >> GO TO 4.
NG >> Refill ATF.
Monitor item Condition Display value
OD CONT SWWhen setting the selector
lever to "4" and "3" posi-
tion.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
4th position
switchM2031 (SB) -
GroundWhen setting
the selector
lever to "4"
and "3" posi-
tion.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0340E
SAT6 3 8A

AT-228
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "1 POSITION SW" switch moving selector lever to
each position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK A/T FLUID LEVEL
Check the A/T fluid level again. Refer to AT- 1 3 , "
Checking A/T Fluid"
.
OK or NG
OK >> GO TO 4.
NG >> Refill ATF.
Monitor item Condition Display value
1 POSITION SWWhen setting the selector
lever to "1" position.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
1st position
switchM2037 (Y/G) -
GroundWhen setting
the selector
lever to "1"
position.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0341E
SAT6 3 8A

AT-230
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
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.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
Vehicle Does Not Decelerate By Engine BrakeUCS002J 2
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-109, "DTC P0705 PARK/NEUTRAL POSITION
SWITCH" , AT-181, "DTC P1845 ATF PRESSURE SWITCH 5" .
NO >> GO TO 2.
2. CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "OVERDRIVE SW" switch moving selector lever to
each position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Monitor item Condition Display value
1 POSITION SWWhen setting the selector
lever to "1" position.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
1st position
switchM2037 (Y/G) -
GroundWhen setting
the selector
lever to "1"
position.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0341E

AT-238
A/T SHIFT LOCK SYSTEM
Revision: August 20072004 QX56
Shift Lock Control Unit Reference ValuesUCS002J 9
SHIFT LOCK HARNESS CONNECTOR TERMINALS LAYOUT
SHIFT LOCK CONTROL UNIT INSPECTION TABLE
Data are reference values.
NOTE:
Confirm that the pointer swings only momentarily because the output time is so short. If the inspection is done with an oscilloscope, it
should be observed that the power source voltage lasts for 3.5 to 10 ms.
LCIA0327E
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONVOLTAGE
(V)
1 Y/R Power sourceIgnition switch: “ON” Battery voltage
Ignition switch: “OFF” Battery voltage
2L/R Detention switch
(for key)When selector lever is not in "P" position with key inserted. Battery voltage
Except the above Approx. 0V
3GRDetention switch
(for shift)When selector lever is not in "P" position Battery voltage
Except the above Approx. 0V
4 R/G Stop lamp switchWhen brake pedal is depressed Battery voltage
When brake pedal is released Approx. 0V
5W/RVehicle speed sig-
nal——
——
6 G/R Ignition signalIgnition switch: “OFF” Approx. 0V
Ignition switch: “ON” Battery voltage
7 R/W Shift lock solenoidWhen brake pedal is depressed with ignition switch "ON". Approx. 0V
When brake pedal is depressed. Battery voltage
8 B Ground — Approx. 0V
9 G/W Key lock solenoidWhen the selector lever is set to a position other than the “P”
position, and the key switch is turned from “ON” to “OFF”Battery voltage for
approx. 0.1 sec.
(Note)
Except the above Approx. 0V
10 W/G Key unlock solenoidWhen ignition switch is not in "ON” position with key inserted.Battery voltage for
approx. 0.1 sec.
(Note)
Except the above Approx. 0V

ATC-24
AIR CONDITIONER CONTROL
Revision: August 20072004 QX56
AIR CONDITIONER CONTROLPFP:27500
DescriptionEJS002BW
The front air control provides automatic regulation of the vehicle's interior temperature. The system is based
on the driver's and passenger's selected "set temperature", regardless of the outside temperature changes.
This is done by utilizing a microcomputer that is part of the front air control, which receives input signals from
the following five sensors:

Ambient sensor

In-vehicle sensor

Intake sensor

Optical sensor (one sensor for driver and passenger side)

PBR (position balanced resistor)
The front air control uses these signals (including the set temperature) to automatically control:

Outlet air volume

Air temperature

Air distribution
The front air control also provides separate regulation of the vehicle's interior temperature for the rear passen-
ger area. The system is based on the temperature and rear blower settings selected on the front air control
rear fan switch (front) and rear temperature/mode dial (front), or from the rear fan switch (rear) and rear tem-
perature/mode dial (rear) on the rear air control, when the rear fan switch (front) is set to the rear (R) position.
The front air control or rear air control is used to select:

Outlet air volume

Air temperature/mode distribution
OperationEJS002BX
AIR MIX DOORS CONTROL
The air mix doors are automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by the temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.
FAN SPEED CONTROL
Blower speed is automatically controlled based on temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of sunload and air mix door position.
When AUTO switch is pressed, the blower motor starts to gradually increase air flow volume (if required).
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flow-
ing.
INTAKE DOOR CONTROL
The intake door is automatically controlled by the temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of sunload and ON-OFF operation of the compressor.
MODE DOOR CONTROL
The mode door is automatically controlled by the temperature setting, ambient temperature, in-vehicle temper-
ature, intake temperature and amount of sunload.
DEFROSTER DOOR CONTROL
The defroster door is controlled by turning the defroster dial to front defroster.

AIR CONDITIONER CONTROL
ATC-25
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Revision: August 20072004 QX56
MAGNET CLUTCH CONTROL
When the A/C or DEF switch is activated, the front air control outputs a compressor ON signal to the BCM.
Upon receiving this input, the BCM sends a compressor ON signal to the ECM via CAN communication lines.
The ECM then judges whether the compressor can be turned ON, based on each sensor status (refrigerant
pressure sensor signal, throttle angle sensor, etc.). If it determines the compressor can be turned ON, a com-
pressor ON signal is sent to the IPDM E/R via CAN communication lines.
Upon receipt of a compressor ON signal, the IPDM E/R turns ON the A/C relay which engages the magnet
clutch and operates the A/C compressor.
SELF-DIAGNOSTIC SYSTEM
A self-diagnostic system is built into the front air control to quickly locate the cause of symptoms. Refer to
ATC-53, "
A/C System Self-diagnosis Function"
WJIA0751E