2009 INFINITI QX56 Abs

EC-66
< FUNCTION DIAGNOSIS >[VK56DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to
EC-456, "DTC Index".
Freeze Frame Data and 1st Trip Freeze Frame Data
EVAP SYSTEM CLOSE CLOSE THE EVAP CANISTER VENT CONTROL VALVE IN
ORDER TO MAKE EVAP SYSTEM CLOSE UNDER THE
FOLLOWING CONDITIONS.
 IGN SW ON
 ENGINE NOT RUNNING
 AMBIENT TEMPERATURE IS ABOVE 0 °C (32 °F).
 NO VACUUM AND NO HIGH PRESSURE IN EVAP SYS- TEM
 FUEL TANK TEMP. IS MORE THAN 0 °C (32 °F).
 WITHIN 10 MINUTES AFTER STARTING “EVAP SYS- TEM CLOSE”
 WHEN TRYING TO EXECUTE “EVAP SYSTEM CLOSE” UNDER THE CONDITION EXCEPT ABOVE, CONSULT-
III WILL DISCONTINUE IT AND DISPLAY APPROPRI-
ATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-III MAY DIS-
PLAY “BATTERY VOLTAGE IS LOW. CHARGE BAT-
TERY”, EVEN IN USING CHARGED BATTERY. When detecting EVAP vapor leak
point of EVAP system
VIN REGISTRATION  IN THIS MODE, VIN IS REGI STERED IN ECM When registering VIN in ECM
TARGET IDLE RPM ADJ*  IDLE CONDITION When setting target idle speed
TARGET IGN TIM ADJ*  IDLE CONDITION Wh en adjusting target ignition tim-
ing
WORK ITEM CONDITION USAGE
Freeze frame data
item* Description
DIAG TROUBLE
CODE
[PXXXX]  The engine control co
mponent part/control system has a trouble code, it is displayed as PXXXX. (Refer to
EC-456, "DTC Index"
.)
FUEL SYS-B1  “Fuel injection system status” at the moment a malfunction is detected is displayed.
 One mode in the following is displayed. Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop
FUEL SYS-B2
CAL/LD VALUE [%]  The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP
[
° C] or [ °F]  The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]  “Long-term fuel trim” at the moment a malfunction is detected is displayed.  The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule than short-term fuel trim.
L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]  “Short-term fuel trim” at the moment a malfunction is detected is displayed.
 The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel sched-
ule.
S-FUEL TRM-B2 [%]
ENGINE SPEED [rpm]  The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph]  The vehicle speed at the moment a malfunction is detected is displayed.
ABSOL TH-P/S
[%]  The throttle valve opening at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]  The base fuel schedule at the moment a malfunction is detected is displayed.
Revision: December 20092009 QX56

P0500 VSSEC-271
< COMPONENT DIAGNOSIS > [VK56DE]
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P0500 VSS
DescriptionINFOID:0000000003771541
NOTE:

If DTC P0500 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-86
.
 If DTC P0500 is displayed with DT C P0607, first perform the trouble diagnosis for DTC P0607. Refer
to EC-284
.
The vehicle speed signal is sent to the combination me ter from the “ABS actuator and electric unit (control
unit)” by CAN communication line. The c combination meter then sends a signal to the ECM by CAN commu-
nication line.
On Board Diagnosis LogicINFOID:0000000003771542
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation ProcedureINFOID:0000000003771543
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Steps 1 and 2 may be conducted with the drive wheels li fted 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 (VDC switch OFF).
2. Read “VHCL SPEED SE” in “DATA MONITOR” m ode with CONSULT-III. The vehicle speed on CON-
SULT-III should exceed 10 km/h (6 MPH) when rotating wheels with suitable gear position.
If NG, go to EC-272, "Diagnosis Procedure"
.
If OK, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Warm engine up to normal operating temperature.
5. Maintain the following conditions for at least 60 consecutive seconds.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0500
0500 Vehicle speed sensor The vehicle speed signal sent to ECM is
almost 0 km/h (0 MPH) even when vehicle
is being driven.  Harness or connectors
(The CAN communication line is open or short-
ed)
 Harness or connectors (The vehicle speed signal circuit is open or
shorted)
 Wheel sensor
 Combination meter
 ABS actuator and electric unit (control unit)
Detected items Engine operating condition in fail-safe mode
Vehicle speed sensor When the fail-safe system for vehicle speed sensor is activated, the cooling fan operates (High) while
engine is running.
ENG SPEED 1,600 - 6,000 rpm
COOLAN TEMP/S More than 70
°C (158 °F)
Revision: December 20092009 QX56

EC-272
< COMPONENT DIAGNOSIS >[VK56DE]
P0500 VSS
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to
EC-272, "Diagnosis Procedure"
.
Overall Function CheckINFOID:0000000003771544
Use this procedure to check the overall function of the v ehicle speed signal circuit. During this check, a 1st trip
DTC might not be confirmed.
WITH GST
1. Lift up drive wheels.
2. Start engine.
3. Read vehicle speed signal in Service $01 with GST. The vehicle speed signal on GST should be able to exceed 10 km/h (6 MPH) when rotating wheels with
suitable gear position.
4. If NG, go to EC-272, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771545
1.CHECK DTC WITH ABS ACTUATOR AN D ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-24, "CONSULT-III Function (ABS)"
.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2.CHECK COMBINATION METER FUNCTION
Refer to MWI-5
.
>> INSPECTION END
B/FUEL SCHDL 6.9 - 31.8 msec
Selector lever Except P or N position
PW/ST SIGNAL OFF
Revision: December 20092009 QX56

EC-296
< COMPONENT DIAGNOSIS >[VK56DE]
P1211 TCS CONTROL UNIT
P1211 TCS CONTROL UNIT
DescriptionINFOID:0000000003771581
The malfunction information related to TCS is trans
ferred through the CAN communication line from “ABS
actuator and electric unit (control unit)” to ECM.
Be sure to erase the malfunction information such as DTC not only for “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagn osis LogicINFOID:0000000003771582
Freeze frame data is not stored in the ECM for this self-diagnosis.
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771583
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
1. Start engine and let it idle for at least 60 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-296, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771584
Go to BRC-24, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1211
1211 TCS control unit
ECM receives a malfunction information from
“ABS actuator electric
unit (control unit)”  ABS actuator and electric unit (control
unit)
 TCS related parts
Revision: December 20092009 QX56

P1212 TCS COMMUNICATION LINEEC-297
< COMPONENT DIAGNOSIS > [VK56DE]
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P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000003771585
NOTE:

If DTC P1212 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-86
.
 If DTC P1212 is displayed with DT C P0607, first perform the trouble diagnosis for DTC P0607. Refer
to EC-284
.
This CAN communication line is used to control the smooth engine operation during the TCS operation. Pulse
signals are exchanged between ECM and “ABS actuator and electric unit (control unit)”.
Be sure to erase the malfunction information such as DTC not only fo r “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagnosis LogicINFOID:0000000003771586
Freeze frame data is not stored in the ECM for this self-diagnosis.
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771587
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-297, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771588
Go to BRC-24, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1212
1212 TCS communication line ECM can not receive the information from
“ABS actuator and electric unit (control
unit)” continuously.  Harness or connectors
(The CAN communication line is open or short-
ed.)
 ABS actuator and electric unit (control unit)
 Dead (Weak) battery
Revision: December 20092009 QX56

EC-344
< COMPONENT DIAGNOSIS >[VK56DE]
P1574 ICC VEHICLE SPEED SENSOR
P1574 ICC VEHICLE SPEED SENSOR
Component DescriptionINFOID:0000000003771648
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:0000000003771649
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-86, "On Board Diagnosis Logic"
.
 If DTC P1574 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-284, "On Board Diagnosis Logic"
.
 If DTC P1574 is displayed with DTC P0500, first pe rform the trouble diagnosis for DTC P0500. Refer
to EC-271, "On Board Diagnosis Logic"
.
 If DTC P1574 is displayed with DTC P0605, first pe rform the trouble diagnosis for DTC P0605. Refer
to EC-282, "On Board Diagnosis Logic"
.
DTC Confirmation ProcedureINFOID:0000000003771650
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
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.
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-344, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771651
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.
2.CHECK DTC WITH “ABS ACTUATOR A ND ELECTRIC UNIT (CONTROL UNIT)”
Refer to BRC-24, "CONSULT-III Function (ABS)"
.
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: December 20092009 QX56

EC-346
< COMPONENT DIAGNOSIS >[VK56DE]
P1574 ASCD VEHICL
E SPEED SENSOR
P1574 ASCD VEHICLE SPEED SENSOR
Component DescriptionINFOID:0000000003771652
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:0000000003771653
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-86, "DTC Confirmation Procedure"
.
 If DTC P1574 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-284, "On Board Diagnosis Logic"
.
 If DTC P1574 is displayed with DTC P0500, first pe rform the trouble diagnosis for DTC P0500. Refer
to EC-271, "On Board Diagnosis Logic"
.
 If DTC P1574 is displayed with DTC P0605, first pe rform the trouble diagnosis for DTC P0605. Refer
to EC-282, "On Board Diagnosis Logic"
.
DTC Confirmation ProcedureINFOID:0000000003771654
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
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.
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-346, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771655
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.
2.CHECK DTC WITH ABS ACTUATOR AN D ELECTRIC UNIT (CONTROL UNIT)
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: December 20092009 QX56

P1574 ASCD VEHICLE SPEED SENSOREC-347
< COMPONENT DIAGNOSIS > [VK56DE]
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Refer to
BRC-24, "CONSULT-III Function (ABS)".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3.CHECK COMBINATION METER FUNCTION
Check combination meter function.
Refer to MWI-5
.
>> INSPECTION END
Revision: December 20092009 QX56