2005 INFINITI QX4 ECU

AT-90
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
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 solenoid
P POSI IND (ON-OFF display) — — XMonitored item (Unit)Monitor Item Selection
Remarks ECU
INPUT
SIGNALSMAIN SIG-
NALSSELEC-
TION
FROM
MENU

TROUBLE DIAGNOSIS
AT-91
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Revision: October 20052005 QX56
R POSI IND (ON-OFF display) — — X
N POSI IND (ON-OFF display) — — X
D POSI IND (ON-OFF display) — — X
4TH POSI IND (ON-OFF display) — — X
3RD POSI IND (ON-OFF display) — — X
2ND POSI IND (ON-OFF display) — — X
1ST POSI IND (ON-OFF display) — — X
MANU MODE IND (ON-OFF display) — — X
Not mounted but displayed.
POWER M LAMP (ON-OFF display) — — X
F-SAFE IND/L (ON-OFF display) — — X
ATF WARN LAMP (ON-OFF display) — — X
BACK-UP LAMP (ON-OFF display) — — X
STARTER RELAY (ON-OFF display) — — X
PNP SW3 MON (ON-OFF display) — — X
C/V CLB ID1 — — X
C/V CLB ID2 — — X
C/V CLB ID3 — — X
UNIT CLB ID1 — — X
UNIT CLB ID2 — — X
UNIT CLB ID3 — — X
TRGT GR RATIO — — X
TRGT PRES TCC (kPa) — — X
TRGT PRES L/P (kPa) — — X
TRGT PRES I/C (kPa) — — X
TRGT PRE FR/B (kPa) — — X
TRGT PRES D/C (kPa) — — X
TRG PRE HLR/C (kPa) — — X
SHIFT PATTERN — — X
DRV CST JUDGE — — X
START RLY MON — — X
NEXT GR POSI — — X
SHIFT MODE — — X
MANU GR POSI — — X
VEHICLE SPEED (km/h) — X X Vehicle speed recognized by the TCM.
Voltage (V) — — XDisplays the value measured by the voltage
probe.
Frequency (Hz) — — X
The value measured by the pulse probe is dis-
played. DUTY-HI (high) (%) — — X
DUTY-LOW (low) (%) — — X
PLS WIDTH-HI (ms) — — X
PLS WIDTH-LOW (ms) — — XMonitored item (Unit)Monitor Item Selection
Remarks ECU
INPUT
SIGNALSMAIN SIG-
NALSSELEC-
TION
FROM
MENU

DTC P0615 START SIGNAL CIRCUIT
AT-99
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Revision: October 20052005 QX56
DTC P0615 START SIGNAL CIRCUITPFP:25230
DescriptionECS00CEW

TCM prohibits cranking other than at “P” or “N” position.
CONSULT-II Reference ValueECS00CEX
On Board Diagnosis LogicECS00CEY

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

Diagnostic trouble code “P0615 STARTER RELAY/CIRC” with CONSULT-II is detected when park/neutral
(PNP) relay (starter relay) is switched “ON” other than at “P” or “N” position. (Or when switched “OFF” at
“P” or “N” position).
Possible CauseECS00CEZ

Harness or connectors
[The park/neutral position (PNP) relay (starter relay) and TCM circuit is open or shorted.]

Park/neutral position (PNP) relay (starter relay)
DTC Confirmation ProcedureECS00CF0
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.
4. Drive vehicle for at least 2 consecutive seconds.
5. If DTC is detected, go to AT - 1 0 1 , "
Diagnostic Procedure" .
Item name Condition Display value
STARTER RELAYSelector lever in “N”,“P” position. ON
Selector lever in other position. OFF
BCIA0030E

DTC P0700 TCM
AT-103
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Revision: October 20052005 QX56
DTC P0700 TCMPFP:31036
DescriptionECS00CLQ
The TCM consists of a microcomputer and connectors for signal input and output and for power supply. The
TCM controls the A/T.
On Board Diagnosis LogicECS00CLR

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P0700 TCM” with CONSULT-II is detected when the TCM is malfunctioning.
Possible CauseECS00CLS
TCM.
DTC Confirmation ProcedureECS00CLT
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.
4. Run engine for at least 2 consecutive seconds at idle speed.
5. If DTC is detected, go to AT - 1 0 3 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Diagnostic ProcedureECS00CLU
1. CHECK DTC
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF DIAG RESULTS” mode for “A/T” with CONSULT-
II.
3. Touch “ERASE”.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Perform DTC Confirmation Procedure, AT-103, "
DTC Confirma-
tion Procedure" .
Is the
“TCM” displayed again?
YES >> Replace the control valve with TCM. Refer to AT-231,
"Control Valve With TCM and A/T Fluid Temperature
Sensor 2" .
NO >>INSPECTION END
BCIA0030E
BCIA0031E

AT-104
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: October 20052005 QX56
DTC P0705 PARK/NEUTRAL POSITION SWITCHPFP:32006
DescriptionECS00CF3

The park/neutral position (PNP) switch includes a transmission position switch.

The transmission range switch detects the selector lever position and sends a signal to the TCM.
CONSULT-II Reference ValueECS00CF4
On Board Diagnosis LogicECS00CF5

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P0705 PNP SW/CIRC” with CONSULT-II is detected under the following condi-
tions.
–When TCM does not receive the correct voltage signal from the PNP switch 1, 2, 3, 4 based on the gear
position.
–When no other position but “P” position is detected from “N” positions.
Possible CauseECS00CF6

Harness or connectors
[The park/neutral position (PNP) switch 1, 2, 3, 4 and TCM circuit is open or shorted.]

Park/neutral position (PNP) switch 1, 2, 3, 4
DTC Confirmation ProcedureECS00CF7
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. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 2
consecutive seconds.
THRTL POS SEN: More than 1.2V
5. If DTC is detected, go to AT-106, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value
SLCTLVR POSI Selector lever in “N”,“P” positions. 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
BCIA0030E

AT-108
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)
Revision: October 20052005 QX56
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)PFP:32702
DescriptionECS00CFA
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 ValueECS00CFB
On Board Diagnosis LogicECS00CFC

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P0720 VEH SPD SEN/CIR AT” with 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 CauseECS00CFD

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

Revolution sensor

Vehicle speed sensor MTR
DTC Confirmation ProcedureECS00CFE
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- 111 , "
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- 111 , "
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- 111 , "
Diagnostic Procedure" .
Item name Condition Display value (km/h)
VHCL/S SE·A/T During driving Approximately matches the speedometer reading.
BCIA0030E

DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)
AT-111
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Revision: October 20052005 QX56
Diagnostic ProcedureECS00CFG
1. CHECK INPUT SIGNAL
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T” with CONSULT-II.
3. Start the engine.
4. Read out the value of “VHCL/S SE·A/T” while driving.
Check the value changes according to driving speed.
OK or NG
OK >> GO TO 6.
NG >> GO TO 2.
2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 8 , "
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 >> GO TO 4.
NG >> Repair or replace damaged parts.
Item name Condition Display value (km/h)
VHCL/S SE·A/T During driving Approximately matches the
speedometer reading.
SCIA2148E

DTC P0725 ENGINE SPEED SIGNAL
AT-113
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Revision: October 20052005 QX56
DTC P0725 ENGINE SPEED SIGNALPFP:24825
DescriptionECS00CFH
The engine speed signal is sent from the ECM to the TCM.
CONSULT-II Reference ValueECS00CFI
On Board Diagnosis LogicECS0 0CF J

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

Diagnostic trouble code “P0725 ENGINE SPEED SIG” with CONSULT-II is detected when TCM does not
receive the ignition signal from ECM during engine cranking or running.
Possible CauseECS00CFK
Harness or connectors
(The ECM to the TCM circuit is open or shorted.)
DTC Confirmation ProcedureECS00CFL
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. Turn ignition switch “ON” and select “DATA MONITOR” mode for
“A/T” with CONSULT-II.
2. Start engine and maintain the following conditions for at least 10
consecutive seconds.
VHCL SPEED SE: 10 km/h (6 MPH) or more
ACCELE POSI: More than 1/8
Selector lever: “D” position
3. If DTC is detected, go to AT - 11 3 , "
Diagnostic Procedure" .
Diagnostic ProcedureECS0 0CF M
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis. Refer to AT - 8 5 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 5 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
Item name Condition Display value (rpm)
ENGINE SPEED Engine running Closely matches the tachometer reading.
BCIA0030E