2005 INFINITI QX4 steering

EC-552Revision: October 2005
DTC P1564 ASCD STEERING SWITCH
2005 QX56
DTC P1564 ASCD STEERING SWITCHPFP:25551
Component DescriptionUBS00L0W
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-29, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for the ASCD function.
CONSULT-II Reference Value in Data Monitor ModeUBS00L0X
Specification data are reference values.
On Board Diagnosis LogicUBS00L0Y
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.
NOTE:
If DTC P1564 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer to
EC-383, "
DTC P0605 ECM".
PBIB2640E
MONITOR ITEM CONDITION SPECIFICATION
MAIN SW

Ignition switch: ONMAIN switch: Pressed ON
MAIN switch: Released OFF
CANCEL SW

Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW

Ignition switch: ONRESUME/ACCELERATE switch: Pressed ON
RESUME/ACCELERATE switch: Released OFF
SET SW

Ignition switch: ONSET/COAST switch: Pressed ON
SET/COAST switch: Released OFF
DTC No. Trouble Diagnosis Name DTC Detecting Condition Possible Cause
P1564
1564ASCD steering switch

An excessively high voltage signal from the ASCD
steering switch is sent to ECM.

ECM detects that input signal from the ASCD
steering 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

DTC P1564 ASCD STEERING SWITCH
EC-553
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Revision: October 20052005 QX56
DTC Confirmation ProcedureUBS00L0Z
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
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. If DTC is detected, go to EC-555, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.

EC-554Revision: October 2005
DTC P1564 ASCD STEERING SWITCH
2005 QX56
Wiring DiagramUBS00L10
BBWA2486E

DTC P1564 ASCD STEERING SWITCH
EC-555
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Revision: October 20052005 QX56
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00L11
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-162, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
67 B Sensor ground[Engine is running]

Warm-up condition

Idle speedApproximately 0V
99 G/Y ASCD steering switch[Ignition switch: ON]

ASCD steering switch: OFFApproximately 4V
[Ignition switch: ON]

MAIN switch: ONApproximately 0V
[Ignition switch: ON]

CANCEL switch: ONApproximately 1V
[Ignition switch: ON]

RESUME/ACCELERATTTE switch: ONApproximately 3V
[Ignition switch: ON]

SET/COAST switch: ONApproximately 2V
BBIA0354E

EC-556Revision: October 2005
DTC P1564 ASCD STEERING SWITCH
2005 QX56
2. CHECK ASCD STEERING SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch ON.
2. Select “MAIN SW”, “CANCEL SW”, RESUME/ACC SW” and “SET SW” in “DATA MONITOR” mode with
CONSULT-II.
3. Check each item indication under the following conditions.
Without CONSULT-II
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 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
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.
Switch Monitor item Condition Indication
MAIN switch MAIN SWPressed ON
Released OFF
CANCEL switch CANCEL SWPressed ON
Released OFF
RESUME/ACCELERATE
switchRESUME/ACC SWPressed ON
Released OFF
SET/COAST switch SET SWPressed ON
Released OFF
SEC0 06 D
Switch Condition Voltage [V]
MAIN switchPressed Approx. 0
Released Approx. 4
CANCEL switchPressed Approx. 1
Released Approx. 4
RESUME/ACCELERATE
switchPressed Approx. 3
Released Approx. 4
SET/COAST switchPressed Approx. 2
Released Approx. 4
PBIB0 311 E
Continuity should exist.
BBIA0362E

DTC P1564 ASCD STEERING SWITCH
EC-557
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Revision: October 20052005 QX56
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors M31, E152

Harness connectors E19, F33

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 SIGNAL 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-558, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace ASCD steering switch. Refer to AV- 4 7 , "
Removal and Installation of Steering Wheel
Audio Control Switches" .
8. CHECK INTERMITTENT INCIDENT
Refer to EC-156, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.

EC-558Revision: October 2005
DTC P1564 ASCD STEERING SWITCH
2005 QX56
Component InspectionUBS00L12
ASCD STEERING SWITCH
1. Disconnect combination switch (spiral cable) harness connector M102.
2. Check continuity between combination switch (spiral cable) ter-
minals 14 and 15 with pushing each switch.
Switch Condition Resistance [Ω]
MAIN switchPressed Approx. 0
Released Approx. 4,000
CANCEL switchPressed Approx. 250
Released Approx. 4,000
RESUME/ACCELERATE
switchPressed Approx. 1,480
Released Approx. 4,000
SET/COAST switchPressed Approx. 660
Released Approx. 4,000
PBIB1673E

DTC P1568 ICC FUNCTION
EC-559
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Revision: October 20052005 QX56
DTC P1568 ICC FUNCTIONPFP:18995
On Board Diagnosis LogicUBS00L1T
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.
NOTE:

If DTC P1568 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-163, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .

If DTC P1568 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-383, "
DTC P0605 ECM".
DTC Confirmation ProcedureUBS00L1U
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 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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Press MAIN switch on ICC steering switch.
4. Drive the vehicle at more than 40 km/h (25 MPH).
5. Press SET/COAST switch.
6. If DTC is detected, go to EC-559, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureUBS00L1V
1. REPLACE ICC UNIT
1. Replace ICC unit.
2. Perform ACS-9, "
ACTION TEST" .
3. Check DTC of ICC unit. Refer to ACS-36, "
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS" .
>>INSPECTION END
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P1568
1568ICC functionECM 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
SEF 0 58 Y