check engine INFINITI QX56 2006 Factory Workshop Manual

AT-124
DTC P1705 THROTTLE POSITION SENSOR
Revision: November 20092006 QX56
DTC P1705 THROTTLE POSITION SENSORPFP:22620
DescriptionECS00CGF
Electric throttle control actuator consists of throttle control motor, accelerator pedal position sensor, throttle
position sensor, etc. The actuator sends a signal to the ECM, and ECM sends signals to TCM with CAN com-
munication.
CONSULT-II Reference ValueECS00CGG
On Board Diagnosis LogicECS00CGH

This is not an OBD-II self-diagnostic item.

Diagnostic trouble code “P1705 TP SEN/CIRC A/T ” with CONSULT-II is detected when TCM does not
receive the proper accelerator pedal position signals (input by CAN communication) from ECM.
Possible CauseECS00CGI
Harness or connectors
(The sensor circuit is open or shorted.)
DTC Confirmation ProcedureECS00CGJ
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. Start engine and let it idle for 1 second.
4. If DTC is detected, go to AT- 1 2 4 , "
Diagnostic Procedure" .
Diagnostic ProcedureECS00CGK
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 6 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
Item name Condition Display value (Approx.)
ACCELE POSI Released accelerator pedal.
0.0/8
Fully depressed accelerator pedal. 8/8
BCIA0030E

DTC P1705 THROTTLE POSITION SENSORAT-125
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Revision: November 2009 2006 QX56
2. CHECK DTC WITH TCM
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 “ACCELE
POSI ”.
4. Select “SELF-DIAG RESULTS” mode for “A/T ” with CONSULT-
II. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" .
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. CHECK DTC WITH ECM
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “ENGINE” with CON-
SULT-II. Refer to AT- 8 4 , "
CONSULT-II Function (A/T)" .
OK or NG
OK >> GO TO 4.
NG >> Check the DTC detected item. Refer to AT- 8 4 , "
CON-
SULT-II Function (A/T)" .

If CAN communication line is detected, go to AT- 9 6 ,
"DTC U1000 CAN COMMUNICATION LINE" .
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 2 4 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 5.
5. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
Item name Condition Display value
(Approx.)
ACCELE POSI Released accelerator pedal.
0.0/8
Fully depressed accelerator pedal. 8/8
PCIA0070E
BCIA0030E

DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUITAT-129
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Revision: November 2009 2006 QX56
Diagnostic ProcedureECS00CGR
1. CHECK A/T FLUID TEMPERATURE SENSOR 1 SIGNAL
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T ” with CONSULT-II.
3. Read out the value of “ATF TEMP SE 1”.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. CHECK A/T FLUID TEMPERATURE SENSOR 2 SIGNAL
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T ” with CONSULT-II.
3. Read out the value of “ATF TEMP SE 2”.
OK or NG
OK >> GO TO 8.
NG >> GO TO 5.
3. CHECK A/T FLUID TEMPERATURE SENSOR 1
Check A/T fluid temperature sensor 1. Refer to AT- 1 3 0 , "
A/T FLUID TEMPERATURE SENSOR 1" .
OK or NG
OK >> GO TO 4.
NG >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "
Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
4. CHECK SUB-HARNESS
1. Disconnect park/neutral position switch connector and TCM connector.
2. Check continuity between park/neutral position switch connector terminals and TCM connector terminals.
3. If OK, check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Replace open circuit or short to ground and short to power in harness or connectors.
Item name Condition °C ( °F) Display value (Approx.)
ATF TEMP SE 1 0 (32) - 20 (68) - 80 (176) 3.3 - 2.7 - 09 V
PCIA0039E
Item name Condition °C ( °F) Display value (Approx.)
ATF TEMP SE 2 0 (32) - 20 (68) - 80 (176) 3.3 - 2.5 - 0.7 V
PCIA0039E
Item Connector Terminal Continuity
Park/neutral position switch
connector F505
6
Ye s
TCM connector F50319
Park/neutral position switch
connector F505
7
Ye s
TCM connector F50318
SCIA5461E

DTC P1721 VEHICLE SPEED SENSOR MTRAT-133
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Revision: November 2009 2006 QX56
Diagnostic ProcedureECS00CH4
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 6 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK INPUT SIGNAL
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T ” with CONSULT-II.
3. Drive vehicle and read out the value of “VHCL/S SE·MTR ”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. CHECK COMBINATION METERS
Check combination meter. Refer to DI-17, "
How to Proceed With Trouble Diagnosis" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 3 2 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 5.
5. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to . AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT"
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector pin terminals for damage or loose connection with harness connec-
tor.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
Item name Condition Display value (Approx.)(km/h)
VHCL/S SE ·MTR During driving Approximately matches the
speedometer reading.
SCIA2148E

AT-138
DTC P1731 A/T 1ST ENGINE BRAKING
Revision: November 20092006 QX56
Diagnostic ProcedureECS00CHG
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start the engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” for
"A/T" with CONSULT-II"
3. Drive vehicle in the “1 ” position (1st gear), and confirm the ON/
OFF actuation of “ATF PRES SW 2 ” and "ON OFF SOL".
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector pin terminals for damage or loose connection with harness connec-
tor.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 3 7 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ON OFF
SOL Low coast brake engaged. Refer to
AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
ATF PRES
SW 2 Low coast brake engaged. Refer to
AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
PCIA0067E

AT-140
DTC P1752 INPUT CLUTCH SOLENOID VALVE
Revision: November 20092006 QX56
Diagnostic ProcedureECS00CHM
1. CHECK INPUT SIGNAL
With CONSULT-II
1. Turn ignition switch “ ON”.
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T”
with CONSULT-II.
3. Start the engine.
4. Read out the value of “I/C SOLENOID” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector pin terminals for damage or loose connection with harness connec-
tor.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 3 9 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
(Approx.)
I/C SOLE-
NOID Input clutch disengaged. Refer to
AT- 2 0
. 0.6 - 0.8 A
Input clutch engaged. Refer to AT- 2 0
. 0 - 0.05 ASCIA4793E

DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTIONAT-141
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Revision: November 2009 2006 QX56
DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTIONPFP:31940
DescriptionECS00CHN

Input clutch solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehi-
cle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be
shifted to the optimum position.

This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical mal-
function such as control valve sticking, improper solenoid valve operation.
CONSULT-II Reference ValueECS00CHO
On Board Diagnosis LogicECS00CHP

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1754 I/C SOLENOID FNCTN” with CONSULT-II is detected under the following
conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
pressure switch 3 is irregular during depressing accelerator pedal. (Other than during shift change)
–When TCM detects that relation between gear position and condition of ATF pressure switch 3 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseECS00CHQ

Harness or connectors
(The solenoid and switch circuits are open or shorted.)

Input clutch solenoid valve

ATF pressure switch 3
DTC Confirmation ProcedureECS00CHR
CAUTION:
Always drive vehicle at a safe speed.
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. Start engine.
2. Accelerate vehicle to maintain the following conditions.
ACCELE POSI: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 3rd
4th Gear (I/C ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3 ” again.
5. Check “SELF-DIAG RESULTS ” mode for “A/T” with CONSULT-
II. If DTC (P1754) is detected, refer to AT- 1 4 2 , "
Diagnostic Procedure" .
If DTC (P1752) is detected, go to AT- 1 4 0 , "
Diagnostic Procedure" .
If DTC (P1843) is detected, go to AT- 1 6 2 , "
Diagnostic Procedure" .
Item nameCondition Display value (Approx.)
I/C SOLENOID Input clutch disengaged. Refer to
AT- 2 0
.0.6 - 0.8 A
Input clutch engaged. Refer to AT- 2 0
.0 - 0.05 A
ATF PRES SW 3 Input clutch engaged. Refer to
AT- 2 0
.ON
Input clutch disengaged. Refer to AT- 2 0
.OFF
BCIA0030E

AT-142
DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION
Revision: November 20092006 QX56
Diagnostic ProcedureECS00CHS
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ ON”. (Do not start engine.)
2. Select “SELECTION FROM MENU ” in “DATA MONITOR” mode
for “A/T ” with CONSULT-II.
3. Start the engine.
4. Drive vehicle in the “D ” position (3rd
4th gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 3 ” and electrical
current value of “I/C SOLENOID”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector pin terminals for damage or loose connection with harness connec-
tor.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 4 1 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
(Approx.)
I/C SOLE-
NOID Input clutch disengaged. Refer to
AT- 2 0
. 0.6 - 0.8 A
Input clutch engaged. Refer to AT- 2 0
. 0 - 0.05 A
ATF PRES
SW 3 Input clutch engaged. Refer to AT- 2 0
.ON
Input clutch disengaged. Refer to AT- 2 0
.OFF
SCIA4795E

AT-144
DTC P1757 FRONT BRAKE SOLENOID VALVE
Revision: November 20092006 QX56
Diagnostic ProcedureECS00CHY
1. CHECK INPUT SIGNAL
With CONSULT-II
1. Turn ignition switch “ ON”.
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T”
with CONSULT-II.
3. Start engine.
4. Read out the value of “FR/B SOLENOID” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 7 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector pin terminals for damage or loose connection with harness connec-
tor.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 3 0 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure ”.

Refer to AT- 1 4 3 , "DTC Confirmation Procedure" .
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
(Approx.)
FR/B SOLE-
NOID Front brake engaged. Refer to AT- 2 0
. 0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
.0 - 0.05 ASCIA4793E

DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTIONAT-145
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Revision: November 2009 2006 QX56
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionECS00CHZ

Front brake solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehi-
cle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be
shifted to the optimum position.

This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical mal-
function such as control valve sticking, improper solenoid valve operation.
CONSULT-II Reference ValueECS00CI0
On Board Diagnosis LogicECS00CI1

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1759 FR/B SOLENOID FNCT ” with CONSULT-II is detected under the follow-
ing conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 1 is irregular during depressing accelerator pedal. (Other than during shift change)
–When TCM detects that relation between gear position and condition of ATF pressure switch 1 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseECS00CI2

Harness or connectors
(The solenoid and switch circuits are open or shorted.)

Front brake solenoid valve

ATF pressure switch 1
DTC Confirmation ProcedureECS00CI3
CAUTION:
Always drive vehicle at a safe speed.
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. Start engine.
2. Accelerate vehicle to maintain the following conditions.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 3rd
4th Gear (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3 ” again.
5. Check “SELF-DIAG RESULTS ” mode for “A/T” with CONSULT-
II. If DTC (P1759) is detected, refer to AT- 1 4 6 , "
Diagnostic Procedure" .
If DTC (P1757) is detected, go to AT- 1 4 4 , "
Diagnostic Procedure" .
If DTC (P1841) is detected, go to AT- 1 6 0 , "
Diagnostic Procedure" .
Item nameCondition Display value (Approx.)
FR/B SOLENOID Front brake engaged. Refer to
AT- 2 0
.0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
.0 - 0.05 A
ATF PRES SW 1 Front brake engaged. Refer to
AT- 2 0
.ON
Front brake disengaged. Refer to AT- 2 0
.OFF
BCIA0030E