2009 INFINITI QX56 steering

EC-328
< COMPONENT DIAGNOSIS >[VK56DE]
P1564 ASCD STEERING SWITCH
P1564 ASCD STEERING SWITCH
Component DescriptionINFOID:0000000003771630
ASCD steering switch has variant values of electrical
resistance for each button. ECM reads voltage variation
of switch, and determines which button is operated.
Refer to EC-33, "System Description"
for the ASCD function.
On Board Diagn osis LogicINFOID:0000000003771631
This self-diagnosis has the one trip detection logic.
 The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1564 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:0000000003771632
1. If DTC Confirmation Procedure has been previously conducted, always perform the following before con-
ducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Wait at least 10 seconds.
4. Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
5. Press CANCEL switch for at least 10 seconds , then release it and wait at least 10 seconds.
6. Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 sec-
onds.
7. Press SET/COAST switch for at least 10 seconds , then release it and wait at least 10 seconds.
8. Check DTC.
9. If DTC is detected, go to EC-328, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771633
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
PBIB2640E
DTC No. Trouble Diagnosi s Name DTC Detecting Co ndition Possible Cause
P1564
1564 ASCD steering switch  An excessively high voltage signal from the ASCD
steering switch is sent to ECM.
 ECM detects that input signal from the ASCD steer- ing switch is out of the specified range.
 ECM detects that the ASCD steering switch is stuck ON.  Harness or connectors
(The switch circuit is open or
shorted.)
 ASCD steering switch
 Combination meter (spiral cable)
ECM
Revision: December 20092009 QX56

P1564 ASCD STEERING SWITCHEC-329
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK ASCD STEERING SWITCH CIRCUIT
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “MAIN SW”, “CANCEL SW”, RESUME/ACC SW” and “SET SW” in “DATA MONITOR” mode with
CONSULT-IIl.
3. Check each item indication under the following conditions.
Without CONSULT-IIl
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 99 and ground with press- ing each button.
OK or NG
OK >> GO TO 8.
NG >> GO TO 3.
3.CHECK ASCD STEERING SWITCH GRO UND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
BBIA0354E
Switch Monitor item Condition Indication
MAIN switch MAIN SW Pressed ON
Released OFF
CANCEL switch CANCEL SW Pressed ON
Released OFF
RESUME/ACCELERATE
switch RESUME/ACC SWPressed ON
Released OFF
SET/COAST switch SET SW Pressed ON
Released OFF
Switch Condition Voltage [V]
MAIN switch Pressed Approx. 0
Released Approx. 4
CANCEL switch Pressed Approx. 1
Released Approx. 4
RESUME/ACCELERATE
switch Pressed Approx. 3
Released Approx. 4
SET/COAST switch Pressed Approx. 2
Released Approx. 4
PBIB0311E
Revision: December 20092009 QX56

EC-330
< COMPONENT DIAGNOSIS >[VK56DE]
P1564 ASCD STEERING SWITCH
2. Disconnect combination switch harness connector M102.
3. Disconnect ECM harness connector.
4. Check harness continuity between combination switch terminal
15 and ECM terminal 67.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors M31, E152
 Harness connectors E5, F14
 Combination switch (spiral cable)
 Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ASCD STEERING SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 99 and combination switch terminal 14. Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors M31, E152
 Combination switch (spiral cable)
 Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK ASCD STEERING SWITCH
Refer to EC-330, "Component Inspection"
.
OK or NG
OK >> GO TO 8.
NG >> Replace ASCD steering switch.
8.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771634
ASCD STEERING SWITCH
1. Disconnect combination switch (spiral cable) harness connector M102. Continuity should exist.
BBIA0362E
Continuity should exist.
Revision: December 20092009 QX56

P1564 ASCD STEERING SWITCHEC-331
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2. Check continuity between combination switch (spiral cable) ter-
minals 14 and 15 with pushing each switch.
Switch Condition Resistance [ Ω]
MAIN switch Pressed Approx. 0
Released Approx. 4,000
CANCEL switch Pressed Approx. 250
Released Approx. 4,000
RESUME/ACCELERATE
switch Pressed Approx. 1,480
Released Approx. 4,000
SET/COAST switch Pressed Approx. 660
Released Approx. 4,000
JMBIA0603ZZ
Revision: December 20092009 QX56

EC-332
< COMPONENT DIAGNOSIS >[VK56DE]
P1568 ICC FUNCTION
P1568 ICC FUNCTION
On Board Diagn
osis LogicINFOID:0000000003771635
This self-diagnosis has the one trip detection logic.
 The MIL will not light up for this self-diagnosis.
NOTE:
 If DTC P1568 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 P1568 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-284, "On Board Diagnosis Logic"
.
 If DTC P1568 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:0000000003771636
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 4 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. Turn ignition switch ON.
2. Press MAIN switch on ICC steering switch.
3. Drive the vehicle at more than 40 km/h (25 MPH).
4. Press SET/COAST switch.
5. Check DTC.
6. If DTC is detected, go to EC-332, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771637
1.REPLACE ICC UNIT
1. Replace ICC unit.
2. Perform CCS-8
.
3. Check DTC of ICC unit. Refer to CCS-18
.
>> INSPECTION END
DTC No. Trouble Diagnosis
Name DTC Detecting Condit
ion Possible Cause
P1568
1568 ICC function
ECM detects a difference between signals
from ICC unit is out of specified range.  Harness or connectors
(The CAN communication line is open or
shorted.)
 ICC unit
ECM
Revision: December 20092009 QX56

ASCD INDICATOREC-387
< COMPONENT DIAGNOSIS > [VK56DE]
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ASCD INDICATOR
Component DescriptionINFOID:0000000003771706
ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and
SET, and is integrated in combination meter.
CRUISE indicator illuminates when MAIN switch on ASCD st
eering switch is turned ON to indicate that ASCD
system is ready for operation.
SET indicator illuminates when following conditions are met.
 CRUISE indicator is illuminated.
 SET/COAST switch on ASCD steering switch is tur ned ON while vehicle speed is within the range of ASCD
setting.
SET indicator remains lit during ASCD control.
Refer to EC-33
for the ASCD function.
Diagnosis ProcedureINFOID:0000000003771707
1.CHECK OVERALL FUNCTION
Check ASCD indicator under the following conditions.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK DTC
Check that DTC U1000 or U1001 is not displayed.
OK or NG
OK >> GO TO 3.
NG >> Perform trouble diagnosis for DTC U1000, U1001. Refer to EC-86
.
3.CHECK COMBINATION METER FUNCTION
Refer to MWI-5
.
OK or NG
OK >> GO TO 4.
NG >> Go to MWI-5
.
4.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
ASCD INDICATOR CONDITION SPECIFICATION
CRUISE LAMP  Ignition switch: ON  MAIN switch: Pressed at the 1st
time → at the 2nd time ON
→ OFF
SET LAMP  MAIN switch: ON
 When vehicle speed is between
40 km/h (25 MPH) and 144 km/h
(89 MPH) ASCD: Operating ON
 ASCD: Not operating OFF
Revision: December 20092009 QX56

ECM
EC-419
< ECU DIAGNOSIS > [VK56DE]
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ECU DIAGNOSIS
ECM
CONSULT-lll Reference Valu
e in Data Monitor ModeINFOID:0000000003771731
Remarks:
z Specification data are reference values.
z Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly relat ed to their components signals/values/operations.
i.e. Adjust ignition timing with a timi ng light before monitoring IGN TIMING, because the monitor may show the specification data in spite of the
ignition timing not being adjusted to the s pecification data. This IGN TIMING monitors the data calculated by the ECM according to the signals
input from the camshaft position sensor an d other ignition timing related sensors.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED  Run engine and compare CONSULT-IIl value with the tachometer indica-
tion. Almost the same speed as the
tachometer indication.
MAS A/F SE-B1 See EC-74
.
B/FUEL SCHDL See EC-74
.
A/F ALPHA-B1
A/F ALPHA-B2 See
EC-74
.
COOLAN TEMP/S  Engine: After warming up More than 70 °C (158 °F)
A/F SEN1 (B1)
A/F SEN1 (B2)  Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 2.2 V
HO2S2 (B1)
HO2S2 (B2)  Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load 0 - 0.3V
←→ Approx. 0.6 - 1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)  Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load LEAN
←→ RICH
VHCL SPEED SE  Turn drive wheels and compare CONSULT-IIl value with the speedometer
indication. Almost the same speed as the
speedometer indication
BATTERY VOLT  Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN 1 Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
ACCEL SEN 2*
1Ignition switch: ON (Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
TP SEN 1-B1
TP SEN 2-B1 Ignition switch: ON
(Engine stopped)
 Selector lever: D Accelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES  Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL  Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG  Engine: After warming up, idle the
engine Air conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)
ON
P/N POSI SW  Ignition switch: ON Selector lever: P or N ON
Selector lever: Except above OFF
PW/ST SIGNAL  Engine: After warming up, idle the
engine Steering wheel: Not being turned
(Forward direction)
OFF
Steering wheel: Being turned ON
Revision: December 20092009 QX56

ECM
EC-423
< ECU DIAGNOSIS > [VK56DE]
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5 L/B Throttle control motor (Open)
[Ignition switch: ON]
 Engine: Stopped
 Selector lever: D
 Accelerator pedal: Fully depressed0 - 14V
6GR Heated oxygen sensor 2 heat-
er (bank 1) [Engine is running]
 Engine speed: Below 3,600 rpm after the
following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load 0 - 1.0V
[Ignition switch: ON]
 Engine: Stopped
[Engine is running]
 Engine speed: Above 3,600 rpm BATTERY VOLTAGE
(11 - 14V)
10 W Intake valve timing control so-
lenoid valve (bank 1) [Engine is running]

Warm-up condition
 Idle speed BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
 Warm-up condition
 Engine speed: 2,000rpm 7 - 12V
11 L G Intake valve timing control so-
lenoid valve (bank 2) [Engine is running]

Warm-up condition
 Idle speed BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
 Warm-up condition
 Engine speed: 2,000rpm 7 - 12V
12 R Power steering pressure sen-
sor [Engine is running]
 Steering wheel: Being turned
0.5 - 4.5V
[Engine is running]
 Steering wheel: Not being turned 0.4 - 0.8V
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
PBIB1105E
PBIB1790E
PBIB1790E
Revision: December 20092009 QX56