Infiniti F50. Manual — part 7

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

ACS-21

[ASCD]

C

D

E

F

G

H

I

J

L

M

A

B

ACS

2.

CHECK STOP LAMP SWITCH CIRCUIT

With CONSULT-II

See “STOP LAMP” in “DATA MONITOR” mode.

Without CONSULT-II

1.

Disconnect ASCD control unit harness connector.

2.

Check voltage between ASCD control unit harness connector
M35 terminal 23 (R/W) and ground.

Refer to wiring diagram in

ACS-10, "FIG. 3"

.

OK or NG

OK

>> ASCD brake/stop lamp switch is OK.

NG

>> Check the following.

●

15A fuse [No. 17, located in the fuse block (J/B) NO.1]

●

Harness for open or short between ASCD control unit and stop lamp switch

●

Harness for open or short between fuse and stop lamp switch

●

Stop lamp switch
Refer to

ACS-29, "Electrical Component Inspection"

.

When brake pedal is released:

STOP LAMP SW OFF

When brake pedal is depressed:

STOP LAMP SW ON

PBIC0207E

When brake pedal is released:

0 V

When brake pedal is depressed:

Approx. 12 V

PBIC0208E

ACS-22

[ASCD]

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

ASCD STEERING SWITCH CHECK

1.

CHECK ASCD STEERING SWITCH CIRCUIT FOR ASCD CONTROL UNIT

With CONSULT-II

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

Without CONSULT-II

Check voltage between ASCD control unit harness connector M35
terminal 11 (G/OR) and ground.

Refer to wiring diagram in

ACS-11, "FIG. 4"

.

OK or NG

OK

>> ASCD steering switch is OK.

NG

>> GO TO 2.

2.

CHECK ASCD STEERING SWITCH

1.

Disconnect ASCD steering switch.

2.

Check resistance between M442 terminals 1 and 2 by depress-
ing each switch.

OK or NG

OK

>> Check harness for open or short between ASCD steering switch and ASCD control unit.

NG

>> Replace ASCD steering switch.

MAIN SW, RESUME/ACC SW,
SET SW and CANCEL SW

When switch is depressed:

ON

When switch is released:

OFF

PBIC0209E

Switch

Condition

Voltage [V]

MAIN (CRUISE) SW

Depressed

0

Released

Approx. 4.0

SET SW

Depressed

Approx. 2.0

Released

Approx. 4.0

RESUME/ACC SW

Depressed

Approx. 3.0

Released

Approx. 4.0

CANCEL SW

Depressed

Approx. 1.0

Released

Approx. 4.0

PBIC0210E

Switch

Condition

Resistance [

Ω

]

MAIN (CRUISE) SW

Depressed

Approx. 0.3

Released

Approx. 4,000

SET SW

Depressed

Approx. 661

Released

Approx. 4,000

RESUME/ACC SW

Depressed

Approx. 1,486

Released

Approx. 4,000

CANCEL SW

Depressed

Approx. 249

Released

Approx. 4,000

PKIA2214E

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

ACS-23

[ASCD]

C

D

E

F

G

H

I

J

L

M

A

B

ACS

VEHICLE SPEED SENSOR CHECK

1.

CHECK SPEEDOMETER OPERATION

Does speedometer operate normally?

Yes

>> GO TO 2.

No

>> Check speedometer and vehicle speed sensor circuit. Refer to

DI-23, "Inspection/Vehicle Speed

Signal"

and

AT-42, "TROUBLE DIAGNOSIS"

.

2.

CHECK VEHICLE SPEED INPUT

With CONSULT-II

See “VHCL SPEED SE” in “DATA MONITOR” mode while driving.

NOTE:

●

This test 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.

●

Always drive vehicle in safe speed and manner according to traffic conditions and obey all traffic laws.

Without CONSULT-II

1.

Apply wheel chocks and jack up drive wheels.

2.

Disconnect ASCD control unit harness connector.

3.

Check voltage between ASCD control unit harness connector M35 terminal 22 (PU/W) and ground with
turning drive wheels slowly by hand.

Refer to wiring diagram in

ACS-12, "FIG. 5"

.

Yes or No

Yes

>> Vehicle speed sensor is OK.

No

>> Check harness for open or short between ASCD control unit harness connector M35 terminal 22

(PU/W) and combination meter harness connector M41 terminal 18 (PU/W).

Is actual vehicle speed indicated?

PBIC0212E

Dose voltage pointer deflect?

PBIC0213E

ACS-24

[ASCD]

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

ASCD PUMP CIRCUIT CHECK

1.

CHECK ASCD PUMP

1.

Disconnect ASCD pump connector.

2.

Measure resistance between ASCD pump terminals 1 and 2, 3, 4.

Refer to wiring diagram in

ACS-11, "FIG. 4"

.

OK or NG

OK

>> GO TO 2.

NG

>> Replace ASCD pump.

2.

CHECK ASCD PUMP CIRCUIT

1.

Disconnect ASCD control unit harness connector.

2.

Check harness for open or short between ASCD control unit and ASCD pump.

OK or NG

OK

>> GO TO 3.

NG

>> Repair harness or connector.

Terminals

Resistance [

Ω

]

1

2

Approx. 65

3

Approx. 65

4

Approx. 3

PBIC0214E

Circuit

Terminal (Wire color)

ASCD control unit

ASCD pump

ASCD pump power supply

12 (R/L)

1 (R/L)

Air valve

13 (L/R)

2 (L/R)

Release valve

1 (L/Y)

3 (L/Y)

Vacuum motor

14 (W/R)

4 (W/R)

Continuity should exist.

PBIC0215E