2009 INFINITI QX56 ECU

TM-58
< COMPONENT DIAGNOSIS >
P0733 3GR INCORRECT RATIO
P0733 3GR INCORRECT RATIO
DescriptionINFOID:0000000003771875
This malfunction is detected when the A/T does not shift into 3GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as
control valve sticking, improper solenoid valve operation.
On Board Diagn osis LogicINFOID:0000000003771876
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P0733” is detected when TCM detec ts any inconsistency in the actual gear ratio.
Possible CauseINFOID:0000000003771877
 Harness or connectors
(Solenoid circuits are open or shorted.)
 Input clutch solenoid valve
 Front brake solenoid valve
 Direct clutch solenoid valve
 High and low reverse clutch solenoid valve
 Each clutch
 Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000003771878
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, alw ays turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Start the engine and select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
2. Make sure that “ATF TEMP 1” is within the following range. ATF TEMP 1: 20 °C – 140 °C
If out of range, drive vehicle to warm ATF or stop engine to cool ATF.
3. Select “3RD GR FNCTN P0733” of “DTC WORK SUPPORT” mode for “TRANSMISSION” with CON-
SULT-III.
4. Drive vehicle and maintain the following conditions.
VEHICLE SPEED: 10 km/h (6 MPH) or more
ACCELE POSI: 0.6/8 or more
ENGINE SPEED: INPUT SPEED − 50 rpm or more
INPUT SPEED: 300 rpm or more
GEAR: “3” position
MANU MODE SW: ON
5. Keep the current driving status for at least 5 consecutive seconds if CONSULT-III screen changes from
“OUT OF CONDITION” to “TESTING”.
CAUTION:
If “TESTING” does not ap pear on CONSULT-III for a long ti me, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0732 is shown, refer to “ TM-117, "DTC No. Index"
”.
If “COMPLETED RESULT NG” is detected, go to TM-59, "Diagnosis Procedure"
.
If “STOP VEHICLE” is detect ed, go to the following step.
6. Stop vehicle.
7. Drive vehicle in “D” position allowing it to shift from 1GR to 5GR and check shift timing and shift shock.
- Touch “OK” to complete the inspection when normally shifted from the 1GR to 5GR.
- Touch “NG” when an unusual shift shock, etc. occurs in spite of shifting from the 1GR to 5GR. Go to TM-
190, "Description".
- Perform TM-32, "CONSULT-III Function (TRANSMISSION)"
when not shifted from the 1GR to 5GR. (Nei-
ther “OK” nor “NG” are indicated.)
Revision: December 20092009 QX56

TM-60
< COMPONENT DIAGNOSIS >
P0734 4GR INCORRECT RATIO
P0734 4GR INCORRECT RATIO
DescriptionINFOID:0000000003771880
This malfunction is detected when the A/T does not shift into 4GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as
control valve sticking, improper solenoid valve operation.
On Board Diagn osis LogicINFOID:0000000003771881
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P0734” is detected when TCM detec ts any inconsistency in the actual gear ratio.
Possible CauseINFOID:0000000003771882
 Harness or connectors
(Solenoid circuits are open or shorted.)
 Input clutch solenoid valve
 Front brake solenoid valve
 Direct clutch solenoid valve
 High and low reverse clutch solenoid valve
 Each clutch
 Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000003771883
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, alw ays turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Start the engine and select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
2. Make sure that “ATF TEMP 1” is within the following range. ATF TEMP 1: 20 °C – 140 °C
If out of range, drive vehicle to warm ATF or stop engine to cool ATF.
3. Select “4TH GR FNCTN P0734” of “DTC WORK SUPPORT” mode for “TRANSMISSION” with CON-
SULT-III.
4. Drive vehicle and maintain the following conditions.
VEHICLE SPEED: 10 km/h (6 MPH) or more
ACCELE POSI: 0.6/8 or more
ENGINE SPEED: INPUT SPEED − 50 rpm or more
INPUT SPEED: 300 rpm or more
GEAR: “4” position
MANU MODE SW: ON
5. Keep the current driving status for at least 5 consecutive seconds if CONSULT-III screen changes from
“OUT OF CONDITION” to “TESTING”.
CAUTION:
If “TESTING” does not ap pear on CONSULT-III for a long ti me, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0734 is shown, refer to “ TM-117, "DTC No. Index"
”.
If “COMPLETED RESULT NG” is detected, go to TM-61, "Diagnosis Procedure"
.
If “STOP VEHICLE” is detect ed, go to the following step.
6. Stop vehicle.
7. Drive vehicle in “D” position allowing it to shift from 1GR to 5GR and check shift timing and shift shock.
- Touch “OK” to complete the inspection when normally shifted from the 1GR to 5GR.
- Touch “NG” when an unusual shift shock, etc. occurs in spite of shifting from the 1GR to 5GR. Go to TM-
190, "Description".
- Perform TM-32, "CONSULT-III Function (TRANSMISSION)"
when not shifted from the 1GR to 5GR. (Nei-
ther “OK” nor “NG” are indicated.)
Revision: December 20092009 QX56

TM-62
< COMPONENT DIAGNOSIS >
P0735 5GR INCORRECT RATIO
P0735 5GR INCORRECT RATIO
DescriptionINFOID:0000000003771885
This malfunction is detected when the A/T does not shift into 5GR position as instructed by TCM. This is not
only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as
control valve sticking, improper solenoid valve operation.
On Board Diagn osis LogicINFOID:0000000003771886
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P0735” is detected when TCM detec ts any inconsistency in the actual gear ratio.
Possible CauseINFOID:0000000003771887
 Harness or connectors
(Solenoid circuits are open or shorted.)
 Input clutch solenoid valve
 Front brake solenoid valve
 Direct clutch solenoid valve
 High and low reverse clutch solenoid valve
 Each clutch
 Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000003771888
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, alw ays turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Start the engine and select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
2. Make sure that “ATF TEMP 1” is within the following range. ATF TEMP 1: 20 °C – 140 °C
If out of range, drive vehicle to warm ATF or stop engine to cool ATF.
3. Select “5TH GR FNCTN P0735” of “DTC WORK SUPPORT” mode for “TRANSMISSION” with CON-
SULT-III.
4. Drive vehicle and maintain the following conditions.
VEHICLE SPEED: 10 km/h (6 MPH) or more
ACCELE POSI: 0.6/8 or more
ENGINE SPEED: INPUT SPEED − 50 rpm or more
INPUT SPEED: 300 rpm or more
GEAR: “5” position
MANU MODE SW: ON
5. Keep the current driving status for at least 5 consecutive seconds if CONSULT-III screen changes from
“OUT OF CONDITION” to “TESTING”.
CAUTION:
If “TESTING” does not ap pear on CONSULT-III for a long ti me, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0735 is shown, refer to “ TM-117, "DTC No. Index"
”.
If “COMPLETED RESULT NG” is detected, go to TM-63, "Diagnosis Procedure"
.
If “STOP VEHICLE” is detect ed, go to the following step.
6. Stop vehicle.
7. Drive vehicle in “D” position allowing it to shif t from 1GR to 5GR gear and check shift timing and shift
shock.
- Touch “OK” to complete the inspection when normally shifted from the 1GR to 5GR.
- Touch “NG” when an unusual shift shock, etc. occurs in spite of shifting from the 1GR to 5GR. Go to TM-
190, "Description".
- Perform TM-32, "CONSULT-III Function (TRANSMISSION)"
when not shifted from the 1GR to 5GR. (Nei-
ther “OK” nor “NG” are indicated.)
Revision: December 20092009 QX56

TM-64
< COMPONENT DIAGNOSIS >
P0740 TORQUE CONVERTER
P0740 TORQUE CONVERTER
DescriptionINFOID:0000000003771890
 The torque converter clutch solenoid valve is activated, with the gear in D4, D5 by the TCM in response to
signals sent from the vehicle speed sensor and accelera tor pedal position sensor (throttle position sensor).
Torque converter clutch piston operation will then be controlled.
 Lock-up operation, however, is prohibited when A/T fluid temperature is too low.
 When the accelerator pedal is depressed (less than 1/8) in lock-up condition, the engine speed should not
change abruptly. If there is a big jump in engine speed, there is no lock-up.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000003771891
On Board Diagnosis LogicINFOID:0000000003771892
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P0740” with CONSULT-III is detected under the following conditions.
- When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
- When TCM detects as irregular by comparing target value with monitor value.
Possible CauseINFOID:0000000003771893
 Torque converter clutch solenoid valve
 Harness or connectors (The solenoid circuit is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000003771894
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 proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-III.
3. Start engine and maintain the following conditions for at least 5 consecutive seconds.
VHCL/S SE-A/T: 80 km/h (50 MPH) or more
ACCELE POSI: 0.5/8 - 1.0/8
SLCT LVR POSI: “D” position
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
4. If DTC is detected go to TM-64, "Diagnosis Procedure"
.
WITH GST
Follow the procedure “With CONSULT-III”.
Diagnosis ProcedureINFOID:0000000003771895
1.CHECK INPUT SIGNAL
With CONSULT-III
1. Turn ignition switch “ON”.
2. Select “MAIN SIGNALS” in “DATA MONITO R” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine.
Item name Condition Display value (Approx.)
TCC SOLENOID When performing slip lock-up 0.2 - 0.4 A
When performing lock-up 0.4 - 0.6 A
Revision: December 20092009 QX56

TM-70
< COMPONENT DIAGNOSIS >
P1705 TP SENSOR
P1705 TP SENSOR
DescriptionINFOID:0000000003771908
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-III Reference Value in Data Monitor ModeINFOID:0000000003771909
On Board Diagn osis LogicINFOID:0000000003771910
 This is not an OBD-II self-diagnostic item.
 Diagnostic trouble code “P1705” with CONSULT-III is detected when TCM does not receive the proper
accelerator pedal position signals (input by CAN communication) from ECM.
Possible CauseINFOID:0000000003771911
Harness or connectors
(The sensor circuit is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000003771912
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 proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to TM-70, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771913
1.CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to TM-32, "CONSULT-III Function (TRANSMISSION)"
.
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to TM-39.
NO >> GO TO 2.
2.CHECK DTC WITH TCM
With CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “ECU INPUT SIGNALS” in “DATA MONI TOR” mode for “TRANSMISSION” with CONSULT-III.
3. Depress accelerator pedal and read out the value of “ACCELE POSI”.
4. Select “SELF-DIAG RESULTS” mode for “T RANSMISSION” with CONSULT-III. Refer to TM-32, "CON-
SULT-III Function (TRANSMISSION)".
Item name Condition Display value (Approx.)
ACCELE POSIReleased accelerator pedal. 0.0/8
Fully depressed accelerator pedal. 8/8
Item name Condition
Display value
(Approx.)
ACCELE POSI Released accelerator pedal. 0.0/8
Fully depressed accelerator pedal. 8/8
Revision: December 20092009 QX56

TM-72
< COMPONENT DIAGNOSIS >
P1710 TRANSMISSION FLUID TEMPERATURE SENSOR
P1710 TRANSMISSION FLUID TEMPERATURE SENSOR
DescriptionINFOID:0000000003771914
The A/T fluid temperature sensor detects the A/ T fluid temperature and sends a signal to the TCM.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000003771915
On Board Diagnosis LogicINFOID:0000000003771916
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P1710 (A/T), P0710 (ENGINE)” with CONSULT-III is detected when TCM receives
an excessively low or high voltage from the sensor.
Possible CauseINFOID:0000000003771917
 Harness or connectors (The sensor circuit is open or shorted.)
 A/T fluid temperature sensors 1
DTC Confirmation ProcedureINFOID:0000000003771918
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 proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-III.
3. Start engine and maintain the following conditions for at least 10 minutes (Total). (It is not necessary to
maintain continuously.)
VHCL/S SE-A/T: 10 km/h (6 MPH) or more
ACCELE POSI: More than 1.0/8
SLCT LVR POSI: “D” position
4. If DTC is detected, go to TM-72, "Diagnosis Procedure"
.
WITH GST
Follow the procedure “With CONSULT-III”.
Diagnosis ProcedureINFOID:0000000003771919
1.CHECK A/T FLUID TEMPERATURE SENSOR 1 SIGNAL
With CONSULT-III
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONI TOR” mode for “TRANSMISSION” with CONSULT-III.
3. Read out the value of “ATF TEMP SE 1”.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
Item name Condition °C ( °F) Display value (Approx.)
ATF TEMP SE 1 0 (32) - 20 (68) - 80 (176) 3.3 - 2.7 - 0.9 V
Item name Condition °C ( °F) Display value (Approx.)
ATF TEMP SE 1 0 (32) - 20 (68) - 80 (176) 3.3 - 2.7 - 0.9 V
Revision: December 20092009 QX56

TM-74
< COMPONENT DIAGNOSIS >
P1721 VEHICLE SPEED SIGNAL
P1721 VEHICLE SPEED SIGNAL
DescriptionINFOID:0000000003771921
The vehicle speed signal is transmitted from combination meter to TCM by CAN communication line. The sig-
nal functions as an auxiliary device to the output speed sensor when it is malfunctioning. The TCM will then
use the vehicle speed signal.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000003771922
On Board Diagn osis LogicINFOID:0000000003771923
 This is not an OBD-II self-diagnostic item.
 Diagnostic trouble code “P1721” with CONSULT-III is det ected when TCM does not receive the proper vehi-
cle speed sensor signal (input by CAN co mmunication) from combination meter.
Possible CauseINFOID:0000000003771924
Harness or connectors
(The sensor circuit is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000003771925
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 proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine and maintain the following conditions for at least 5 consecutive seconds. ACCELE POSI: 1/8 or less
VHCL/S SE-MTR: 30 km/h (17 MPH) or more
4. If DTC is detected, go to TM-74, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771926
1.CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer TM-32, "CONSULT-III Function (TRANSMISSION)"
.
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to TM-39.
NO >> GO TO 2.
2.CHECK INPUT SIGNAL
With CONSULT-III
1. Start engine.
2. Select “ECU INPUT SIGNALS” in “DATA MONI TOR” mode for “TRANSMISSION” with CONSULT-III.
3. Drive vehicle and read out the value of “VHCL/S SE·MTR”.
OK or NG
Item name Condition Display value (km/h)
VHCL/S SE·MTR During driving Approximately matches the speedometer reading.
Item name Condition Displa y value (Approx.)(km/h)
VHCL/S SE·MTR During driving Approximately matches the speed-
ometer reading.
Revision: December 20092009 QX56

TM-76
< COMPONENT DIAGNOSIS >
P1730 INTERLOCK
P1730 INTERLOCK
DescriptionINFOID:0000000003771927
 Fail-safe function to detect interlock conditions.
On Board Diagnosis LogicINFOID:0000000003771928
 This is an OBD-II self-diagnostic item.
 Diagnostic trouble code “P1730” with CONSULT-III is detected when TCM does not receive the proper volt-
age signal from the sensor and switch.
 TCM monitors and compares gear position and conditions of each ATF pressure switch when gear is steady.
Possible CauseINFOID:0000000003771929
 Harness or connectors
(The solenoid and switch circuit is open or shorted.)
 Low coast brake solenoid valve
 ATF pressure switch 2
DTC Confirmation ProcedureINFOID:0000000003771930
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 proc edure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 2 consecutive seconds. SLCT LVR POSI: “D” position
5. If DTC is detected, go to TM-76, "Diagnosis Procedure"
.
WITH GST
Follow the procedure “With CONSULT-III”.
Judgement of InterlockINFOID:0000000003771931
 When Interlock is judged to be malfunctioning, the vehi cle should be fixed in 2GR, and should be set in a
condition in which it can travel.
NOTE:
When the vehicle is driven fixed in 2GR, an input speed s ensor malfunction is displayed, but this is not a input
speed sensor malfunction.
 When interlock is detected at the 3GR or more, it is locked at the 2GR.
Diagnosis ProcedureINFOID:0000000003771932
1.SELF-DIAGNOSIS
With CONSULT-III
1. Drive vehicle.
2. Stop vehicle and turn ignition switch “OFF”.
3. Turn ignition switch “ON”.
4. Select “SELF-DIAG RESULTS” mode fo r “TRANSMISSION” with CONSULT-III.
OK or NG
OK >> GO TO 2.
NG >> Check low coast brake solenoid valve circuit and function. Refer to TM-88, "Diagnosis Proce-
dure", TM-90, "Diagnosis Procedure".
2.CHECK DTC
Perform “DTC Confirmation Procedure”.
Revision: December 20092009 QX56