Nissan Quest E52. Manual - part 538

EC-362

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1564 ASCD STEERING SWITCH

P1564 ASCD STEERING SWITCH

DTC Logic

INFOID:0000000009651210

DTC DETECTION LOGIC

NOTE:
If DTC P1564 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605. Refer to

EC-335, "DTC Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next test. 
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON and wait at least 10 seconds.

2.

Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.

3.

Press CANCEL switch for at least 10 seconds, then release it and wait at least 10 seconds.

4.

Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 sec-
onds.

5.

Press SET/COAST switch for at least 10 seconds, then release it and wait at least 10 seconds.

6.

Check DTC.

Is DTC detected?

YES

>> Proceed to 

EC-362, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009651211

1.

CHECK ASCD STEERING SWITCH CIRCUIT

 With CONSULT

1.

Turn ignition switch ON.

2.

Select “MAIN SW”, “CANCEL SW”, “RESUME/ACC SW” and “SET SW” in “DATA MONITOR” mode with
CONSULT.

3.

Check each item indication under the following conditions.

DTC No.

Trouble diagnosis 

name

DTC detecting condition

Possible cause

P1564

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 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
• ECM

Monitor item

Condition

Indication

MAIN SW

MAIN switch

Pressed

ON

Released

OFF

CANCEL SW

CANCEL switch

Pressed

ON

Released

OFF

P1564 ASCD STEERING SWITCH

EC-363

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 Without CONSULT

1.

Turn ignition switch ON.

2.

Check the voltage between ECM harness connector terminals under the following conditions.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-42, "Intermittent Incident"

.

NO

>> GO TO 2.

2.

CHECK ASCD STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector M303.

3.

Disconnect combination switch harness connector.

4.

Check the continuity between combination switch and ECM harness connector.

5.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace error-detected parts.

3.

CHECK ASCD STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between combination switch and ECM harness connector.

2.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK ASCD STEERING SWITCH

Check ASCD steering switch. Refer to 

EC-364, "Component Inspection"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-42, "Intermittent Incident"

.

RESUME/ACC SW

RESUME/ACCEL-
ERATE switch

Pressed

ON

Released

OFF

SET SW

SET/COAST switch

Pressed

ON

Released

OFF

ECM

Condition

Voltage (V)

Con-

nector

+

–

Terminal

Terminal

E16

101

(ASCD steering switch 

signal)

108

(ASCD steering switch 

ground)

MAIN switch: Pressed

Approx. 0

CANCEL switch: Pressed

Approx. 1

SET/COAST switch: Pressed

Approx. 2

RESUME/ACCELERATE switch: Pressed

Approx. 3

All ASCD steering switches: Released

Approx. 4

Monitor item

Condition

Indication

Combination switch

ECM

Continuity

Terminal

Connector

Terminal

16

E16

108

Existed

Combination switch

ECM

Continuity

Terminal

Connector

Terminal

13

E16

101

Existed

EC-364

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1564 ASCD STEERING SWITCH

NO

>> Replace ASCD steering switch. Refer to 

EC-15, "ENGINE CONTROL SYSTEM : Component

Parts Location"

.

Component Inspection

INFOID:0000000009651212

1.

CHECK ASCD STEERING SWITCH

1.

Turn ignition switch OFF.

2.

Disconnect combination switch (spiral cable) harness connector.

3.

Check resistance between combination switch harness connector terminals as per the following.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace ASCD steering switch

Combination switch

Condition

Resistance (

Ω

)

Connector

Terminals

M33

13 and 16

MAIN switch: Pressed

Approx. 0

CANCEL switch: Pressed

Approx. 250

SET/COAST switch: Pressed

Approx. 660

RESUME/ACCELERATE switch: Pressed

Approx. 1,480

All ASCD steering switches: Released

Approx. 4,000

P1572 ASCD BRAKE SWITCH

EC-365

< DTC/CIRCUIT DIAGNOSIS >

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P1572 ASCD BRAKE SWITCH

Description

INFOID:0000000009651213

When the brake pedal is depressed, ASCD 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 

EC-44, "AUTOMATIC SPEED CONTROL DEVICE (ASCD) : System Description"

 for the ASCD func-

tion.

DTC Logic

INFOID:0000000009651214

DTC DETECTION LOGIC

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

to 

EC-335, "DTC Logic"

.

• 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.

DTC CONFIRMATION PROCEDURE

1.

INSPECTION START

Do you have CONSULT?

Do you have CONSULT?

YES

>> GO TO 2.

NO

>> GO TO 5.

2.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
NOTE:
Procedure for malfunction B is not described here. It takes extremely long time to complete procedure for mal-
function B. By performing procedure for malfunction A, the incident that causes malfunction B can be
detected.

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A-I

1.

Start engine (VDC switch OFF).

2.

Select “DATA MONITOR” mode with CONSULT.

3.

Press MAIN switch and make sure that CRUISE lamp lights up.

4.

Drive the vehicle for at least 5 consecutive seconds under the following conditions.

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
This procedure 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.

DTC No.

Trouble diagnosis 

name

DTC detecting condition

Possible cause

P1572

ASCD brake switch

A)

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

• Harness or connectors

(The stop lamp switch circuit is shorted.)

• Harness or connectors

(The ASCD brake switch circuit is shorted.)

• Stop lamp switch
• ASCD brake switch
• Incorrect stop lamp switch installation
• Incorrect ASCD brake switch installation
• ECM

B)

ASCD brake switch signal is not sent to 
ECM for extremely long time while the ve-
hicle is driving.