2008 INFINITI QX56 transmission

U1000, U1001 CAN COMM CIRCUITEC-87
< COMPONENT DIAGNOSIS > [VK56DE]
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U1000, U1001 CAN COMM CIRCUIT
DescriptionINFOID:0000000001351359
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each
control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagnosis LogicINFOID:0000000001351360
*1: This self-diagnosis has the one trip detection logic.
*2: The MIL will not light up for this self-diagnosis.
*3: This self-diagnosis has the one or two trip detection logic (Models with ICC)
DTC Confirmation ProcedureINFOID:0000000001351361
1. Turn ignition switch ON and wait at least 3 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-87, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001351363
Go to LAN-44, "CAN Communication Signal Chart".
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
U1000*
1
1000*1
CAN communication line When ECM is not transmitting or receiving CAN
communication signal of OBD (emission-relat-
ed diagnosis) for 2 seconds or more.
• Harness or connectors
(CAN communication line is open or
shorted)
U1001*2*3
1001*2*3
When ECM is not transmitting or receiving CAN
communication signal other than OBD (emis-
sion related diagnosis) for 2 seconds or more.
Revision: March 2010 2008 QX56

EC-88
< COMPONENT DIAGNOSIS >[VK56DE]
U1010 CONTROL UNIT (CAN)
U1010 CONTROL UNIT (CAN)
DescriptionINFOID:0000000001351364
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication s
peed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CA N communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagn osis LogicINFOID:0000000001351365
This self-diagnosis has the one trip detection logic.
DTC Confirmation ProcedureINFOID:0000000001351366
WITH CONSULT-III
1. Turn ignition switch ON.
2. Check DTC.
3. If DTC is detected, go to EC-88, "
Diagnosis Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351367
1.INSPECTION START
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELF-DIAG RESULTS” mode with CONSULT-III.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-88, "
DTC Confirmation Procedure" .
5. Is the DTC U1010 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-88, "
DTC Confirmation Procedure" .
4. Is the DTC U1010 displayed again?
Ye s o r N o
Ye s > > G O T O 2 .
No >> INSPECTION END
2.REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS (NATS) system and regist ration of all IVIS (NATS) ignition key IDs. Refer to
SEC-8, "
ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement".
3. Perform EC-17, "
VIN Registration" .
4. Perform EC-18, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-18, "
Throttle Valve Closed Position Learning" .
6. Perform EC-18, "
Idle Air Volume Learning" .
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
U1010
1010 CAN communication bus When detecting error during the initial diagno-
sis of CAN controller of ECM.
•ECM
Revision: March 2010
2008 QX56

EC-296
< COMPONENT DIAGNOSIS >[VK56DE]
P0850 PNP SWITCH
P0850 PNP SWITCH
Component DescriptionINFOID:0000000001351688
When the gear position is P or N, transmission range switch is ON.
TCM detects the position because the conti
nuity of the line (the ON signal) exists.
Then the TCM sends the PNP signal to the ECM via combination meter.
On Board Diagn osis LogicINFOID:0000000001351690
DTC Confirmation ProcedureINFOID:0000000001351691
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “P/N POSI SW” in “DATA MONITOR” mode with CONSULT-III. Then check the “P/N POSI SW” sig-
nal under the following conditions.
If NG, go to EC-297, "
Diagnosis Procedure".
If OK, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Start engine and warm it up to normal operating temperature.
5. Maintain the following conditions for at least 60 consecutive seconds.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-297, "
Diagnosis Procedure".
Overall Function CheckINFOID:0000000001351692
Use this procedure to check the overall function of t he park/neutral position (PNP) signal circuit. During this
check, a 1st trip DTC might not be confirmed.
WITH GST
1. Turn ignition switch ON.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0850
0850 Park/neutral position
switch The park/neutral position (PNP) signal is not
changed in the process of engine starting and
driving. • Harness or connectors
[The park/neutral position (PNP) signal
circuit is open or shorted.]
• Combination meter
•TCM
Position (Selector lever) Known-good signal
N or P position ON
Except the above position OFF
ENG SPEED1,000 - 6,375 rpm
COOLAN TEMP/S More than 70°C (158 °F)
B/FUEL SCHDL 2.0 - 31.8 msec
VHCL SPEED SE More than 64 km/h (40 MPH)
Selector lever Suitable position
Revision: March 2010 2008 QX56

EC-352
< COMPONENT DIAGNOSIS >[VK56DE]
P1574 ICC VEHICLE SPEED SENSOR
P1574 ICC VEHICLE
SPEED SENSOR
Component DescriptionINFOID:0000000001528791
The ECM receives two vehicle speed signals via CAN communication line. One is sent from “unified meter and
A/C amp.”, and the other is from TCM (Transmission control module). The ECM uses these signals for ICC
control. Refer to CCS-13
for ICC functions.
On Board Diagnosis LogicINFOID:0000000001528792
•This self-diagnosis has the one trip detection logic.
• The MIL will not light up for this self-diagnosis.
NOTE:
• If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-87, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DTC P0500, first perform the trouble diagno sis for DTC P0500. Refer
to EC-280, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DTC P0605, first perform the trouble diagno sis for DTC P0605. Refer
to EC-291, "
On Board Diagnosis Logic".
DTC Confirmation ProcedureINFOID:0000000001528793
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Step 3 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Start engine.
2. Drive the vehicle at more than 40 km/h (25MPH).
3. Check 1st trip DTC.
4. If DTC is detected, go to EC-352, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001528794
1.CHECK DTC WITH TCM
Check DTC with TCM. Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
OK or NG
OK >> GO TO 2.
NG >> Perform trouble shooting relevant to DTC indicated.
DTC No. Trouble Diagnosis Name DTC Detecting Condition Possible Cause
P1574
1574 ICC vehicle speed sensor ECM detects a difference between two vehicle
speed signals is out of the specified range. • Harness or connectors
(The CAN communication line is open or
shorted.)
• Combination meter
• ABS actuator and electric unit (control unit)
• Wheel sensor
•TCM
•ECM
Revision: March 2010 2008 QX56

EC-354
< COMPONENT DIAGNOSIS >[VK56DE]
P1574 ASCD VEHICLE SPEED SENSOR
P1574 ASCD VEHICLE SPEED SENSOR
Component DescriptionINFOID:0000000001365781
The ECM receives two vehicle speed sensor signals via CAN communication line. One is sent from combina-
tion meter and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD
control. Refer to
EC-33, "
System Description" for ASCD functions.
On Board Diagnosis LogicINFOID:0000000001365782
•This self-diagnosis has the one trip detection logic.
• The MIL will not light up for this self-diagnosis.
NOTE:
• If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-87, "
DTC Confirmation Procedure" .
• If DTC P1574 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88, "
On Board Diagnosis Logic" .
• If DTC P1574 is displayed with DTC P0500, first perform the trouble diagno sis for DTC P0500. Refer
to EC-280, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DTC P0605, first perform the trouble diagno sis for DTC P0605. Refer
to EC-291, "
On Board Diagnosis Logic".
DTC Confirmation ProcedureINFOID:0000000001365783
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Step 3 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-IIl
1. Start engine (VDC switch OFF).
2. Drive the vehicle at more than 40 km/h (25 MPH).
3. Check DTC.
4. If DTC is detected, go to EC-354, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-lII” above.
Diagnosis ProcedureINFOID:0000000001365784
1.CHECK DTC WITH TCM
Check DTC with TCM. Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
OK or NG
OK >> GO TO 2.
NG >> Perform trouble shooting relevant to DTC indicated.
DTC No. Trouble Diagnosis
Name DTC Detecting Condit
ion Possible Cause
P1574
1574 ASCD vehicle speed
sensor ECM detects a difference between two vehicle
speed signals is out of the specified range. • Harness or connectors
(The CAN communication line is open or
shorted.)
• Combination meter
• ABS actuator and electric unit (control unit)
• Wheel sensor
•TCM
•ECM
Revision: March 2010 2008 QX56

ECM
EC-461
< ECU DIAGNOSIS > [VK56DE]
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DTC Inspection Priority ChartINFOID:0000000001351338
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
•
If DTC U1000 and/or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC U1010 is displayed with ot her DTC, first perform the trouble diagnosis for DTC U1010. Refer to
EC-88
.
Priority Detected items (DTC)
1 • U1000 U1001 CAN communication line • U1010 CAN communication
• P0101 P0102 P0103 Mass air flow sensor
• P0112 P0113 P0127 Intake air temperature sensor
• P0116 P0117 P0118 P0125 Engine coolant temperature sensor
• P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
• P0128 Thermostat function
• P0181 P0182 P0183 Fuel tank temperature sensor
• P0327 P0328 P0332 P0333 Knock sensor
• P0335 Crankshaft position sensor (POS)
• P0340 Camshaft posi tion sensor (PHASE)
• P0460 P0461 P0462 P0463 Fuel level sensor
• P0500 Vehicle speed sensor
• P0605 ECM
• P0643 Sensor power supply
• P0700 TCM
• P0705 Transmission range switch
• P0850 Park/neutral position (PNP) switch
• P1550 P1551 P1552 P1553 P1554 Battery current sensor
• P1610 - P1615 NATS
• P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
Revision: March 2010 2008 QX56

EC-464
< ECU DIAGNOSIS >[VK56DE]
ECM
CYL 1 MISFIRE
P03010301—2×EC-198
CYL 2 MISFIRE P03020302—2×EC-198
CYL 3 MISFIRE P03030303—2×EC-198
CYL 4 MISFIRE P03040304—2×EC-198
CYL 5 MISFIRE P03050305—2×EC-198
CYL 6 MISFIRE P03060306—2×EC-198
CYL 7 MISFIRE P03070307—2×EC-198
CYL 8 MISFIRE P03080308—2×EC-198
KNOCK SEN/CIRC-B1 P03270327—2—EC-204
KNOCK SEN/CIRC-B1 P03280328—2—EC-204
KNOCK SEN/CIRC-B2 P03320332—2—EC-204
KNOCK SEN/CIRC-B2 P03330333—2—EC-204
CKP SEN/CIRCUIT P03350335—2×EC-207
CMP SEN/CIRC-B1 P03400340—2×EC-211
TW CATALYST SYS-B1 P04200420 ×2 ×EC-215
TW CATALYST SYS-B2 P04300430 ×2 ×EC-215
EVAP PURG FLOW /MON P0441 0441 ×2 ×EC-219
EVAP SMALL LEAK P04420442 ×2 ×EC-224
PURG VOLUME CONT/V P04430443—2×EC-231
PURG VOLUME CONT/V P04440444—2×EC-236
PURG VOLUME CONT/V P04450445—2×EC-236
VENT CONTROL VALVE P04470447—2×EC-239
VENT CONTROL VALVE P04480448—2×EC-243
EVAP SYS PRES SEN P04510451—2×EC-247
EVAP SYS PRES SEN P04520452—2×EC-250
EVAP SYS PRES SEN P04530453—2×EC-254
EVAP GROSS LEAK P04550455—2×EC-259
EVAP VERY SML LEAK P04560456
×*42 ×EC-266
FUEL LEV SEN SLOSH P04600460—2×EC-274
FUEL LEVEL SENSOR P04610461—2×EC-276
FUEL LEVL SEN/CIRC P04620462—2×EC-278
FUEL LEVL SEN/CIRC P04630463—2×EC-278
VEH SPEED SEN/CIRC*6P0500 0500—2×EC-280
ISC SYSTEM P05060506—2×EC-282
ISC SYSTEM P05070507—2×EC-284
PW ST P SEN/CIRC P05500550—2—EC-286
ECM BACK UP/CIRC P06030603—2×EC-289
ECM P06050605—1 or 2 × or — EC-291
SENSOR POWER/CIRC P06430643—1×EC-293
TRANSMISSION CONT P07000700—1×TM-42
T/M RANGE SENSOR A P07050705—2×TM-43
ATF TEMP SEN/CIRC P07100710—2×TM-71
Items
(CONSULT-IIl screen terms) DTC*
1
SRT code Trip
MILReference
page
CONSULT-IIl
GST*
2ECM*3
Revision: March 2010 2008 QX56

PRECAUTIONSEC-487
< PRECAUTION > [VK56DE]
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5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000001351222
The ECM has an on board diagnostic system . It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch OFF and di sconnect the negative battery cable before any repair
or inspection work. The open/short circuit of re lated switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For description and how to disconnect, refer to PG-65
.
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit.
• Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfuncti on of the EVAP system or fuel injection system,
etc.
• Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionINFOID:0000000006211821
•Always use a 12 volt battery as power source.
• Do not attempt to disconnect battery cables while engine is
running.
• Before connecting or disc onnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
• Before removing parts, turn ig nition switch OFF and then dis-
connect negative battery cable.
• Do not disassemble ECM.
• If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to sel f-control at its initial value.
Engine operation can vary slight ly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.
• If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
-
Presumed ethanol mixture ratio
SEF289H
PBIB1164E
Revision: March 2010 2008 QX56