Infiniti Q45. Manual - part 488

DTC P1564 ASCD STEERING SWITCH

EC-591

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4. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M135, F105

●

Combination switch (spiral cable)

●

Harness for open and short between ECM and ASCD steering 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 ASCD steering switch terminal 1.
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 M135, F105

●

Combination switch (spiral cable)

●

Harness for open and short between ECM and ASCD steering switch

>> Repair open circuit or short to ground or short to power in harness or connectors.

7. 

CHECK ASCD STEERING SWITCH

Refer to 

EC-592, "Component Inspection"

 .

OK or NG

OK

>> GO TO 8.

NG

>> Replace ASCD steering switch.

8. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-145, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END

Continuity should exist.

EC-592

DTC P1564 ASCD STEERING SWITCH

Component Inspection

NBS00248

ASCD STEERING SWITCH

1.

Disconnect ASCD steering switch.

2.

Check continuity between ASCD steering switch terminals 1 and
2 with pushing each switch.

If NG, replace ASCD steering 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

SEC008D

DTC P1568 ICC FUNCTION

EC-593

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DTC P1568 ICC FUNCTION

PFP:18995

On Board Diagnosis Logic

NBS00249

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-156, "DTC U1000, U1001 CAN COMMUNICATION LINE"

 .

●

If DTC P1568 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to 

EC-159, "DTC U1010 CAN COMMUNICATION"

 .

●

If DTC P1568 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to 

EC-489, "DTC P0605 ECM"

 .

DTC Confirmation Procedure

NBS0024A

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-593, "Diagnostic Procedure"

 .

 WITH GST

Follow the procedure “WITH CONSULT-II” above.

Diagnostic Procedure

NBS0024B

1. 

REPLACE ICC UNIT

1.

Replace ICC unit.

2.

Perform 

ACS-11, "ACTION TEST"

 .

3.

Check DTC of ICC unit. Refer to 

ACS-43, "TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS"

 .

>> INSPECTION END

DTC No.

Trouble Diagnosis 

Name

DTC Detecting Condition

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.)

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ICC unit

●

ECM

SEF058Y

EC-594

DTC P1572 ICC BRAKE SWITCH

DTC P1572 ICC BRAKE SWITCH

PFP:25320

Component Description

NBS0024C

When the brake pedal is depressed, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal).
Refer to 

ACS-6, "DESCRIPTION"

  for the ICC function.

CONSULT-II Reference Value in Data Monitor Mode

NBS0024D

Specification data are reference values.

On Board Diagnosis Logic

NBS0024E

This diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.

NOTE:

●

If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to 

EC-489

 .

●

This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two
consecutive trips, DTC is not stored in ECM memory.

PBIB2433E

MONITOR ITEM

CONDITION

SPECIFICATION

BRAKE SW1
(ICC brake switch)

●

Ignition switch: ON

Brake pedal: Fully released

ON

Brake pedal: Slightly depressed

OFF

BRAKE SW2
(stop lamp switch)

●

Ignition switch: ON

Brake pedal: Fully released

OFF

Brake pedal: Slightly depressed

ON

DTC No.

Trouble diagnosis 

name

DTC detecting condition

Possible cause

P1572
1572

ICC brake switch

A)

When the vehicle speed is above 30 km/h 
(19 MPH), ON signals from the stop lamp 
switch and the ICC brake switch are sent 
to ECM at the same time.

●

Harness or connectors
(The stop lamp switch circuit is shorted.)

●

Harness or connectors
(The ICC brake switch circuit is shorted.)

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Stop lamp switch

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ICC brake switch

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ICC brake hold relay

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Incorrect stop lamp switch installation

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Incorrect ICC brake switch installation

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ECM

B)

ICC brake switch signal is not sent to ECM 
for extremely long time while the vehicle is 
driving