Subaru Legacy III (2000-2003 year). Manual — part 999

CC-16

CRUISE CONTROL SYSTEM (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SYMPTOM

C: CHECK CRUISE CONTROL MAIN SWITCH

TROUBLE SYMPTOM:
Cruise control main switch is not turned ON and cruise control cannot be set.

NOTE:
When the main relay (built-in cruise control module) operates, the main switch circuit is in normal condition.
The main relay operation can be checked by hearing the operation sounds.
This operation sounds will be heard when ignition switch and cruise control main switch is turned to ON.
WIRING DIAGRAM:

M2

B2

A2

1

11

15

12

6

i1

B36

CRUISE CONTROL MODULE

B94

BATTERY

IGNITION

SWITCH

6

1

5

3

NO. 18

SBF-4

i19

SMJ

CRUISE CONTROL

MAIN SWITCH

i19

1
3 4 5 6

2

B94

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

B36

B4 B5 B6

A4 A5 A6

C5 C6

F6

D4 D5 D6

F1

H1

C4

G6

G1

C2

K1

M1 M2

K6

L1

D1 D2

A1 A2
B1 B2

I6

J6

L2

I1

J1

H6

M4 M5 M6

L4 L5 L6

N5 N6

O4 O5 O6

N4

P4 P5

N2

O1 O2

P1 P2

N3

O3

P3

P6

A3

B3

C3

E4 E5 E6

E1 E2

3

1

11

9

i60

i61

CC-00096

B

A

B

A

B

A

B

A

B

A

B

A

B

A

B

B

A

: LHD H6 AND LHD H4 FOR
EUROPE

: LHD H4 EXCEPT FOR EUROPE
AND RHD

A

B

1 2 3
9 10

4

11 12 13 14 15 16

5 6 7

17 18

8

i60

CC-17

CRUISE CONTROL SYSTEM (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SYMPTOM

Step

Value

Yes

No

1

CHECK CRUISE CONTROL MAIN SWITCH
CIRCUIT.
1) Turn ignition switch OFF.
2) Disconnect cruise control main switch har-

ness connector.

3) Turn ignition switch ON.
4) Measure voltage between harness connec-

tor terminal and chassis ground.

Connector & terminal

(i19) No. 3 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 2.

• Check fuse No.
18 (in fuse & relay
box).
• Check harness
for open or short
between cruise
control main
switch and fuse &
relay box.

2

CHECK CRUISE CONTROL MAIN SWITCH
CIRCUIT.
1) Turn ignition switch OFF.
2) Disconnect cruise control module harness

connector.

3) Measure resistance between cruise control

module harness connector terminal and
cruise control main switch harness connec-
tor terminal.

Connector & terminal

(B94) No. 15 — (i19) No. 5:
(B94) No. 1 — (i19) No. 6:
(B94) No. 11 — (i19) No. 1:

Is the measured value less than the speci-
fied value?

10

Ω

Go to step 3.

Repair harness.

3

CHECK CRUISE CONTROL MAIN SWITCH.
Remove and check cruise control main switch.
<Ref. to CC-7, Cruise Control Main Switch.>
Is cruise control main switch OK?

Cruise control main switch is
OK.

Replace cruise
control module.

Replace cruise
control main
switch.

CC-18

CRUISE CONTROL SYSTEM (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SYMPTOM

D: CHECK CRUISE CONTROL COMMAND SWITCH

TROUBLE SYMPTOM:
Cruise control cannot be set. (Cancelled immediately.)
WIRING DIAGRAM:

CC-00097

3

2

1

9

10

F2

CRUISE CONTROL
MODULE

B94

BATTERY

5

M/B NO. 6

S1

B100

B94

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

F2

RESUME/

ACCEL

SWITCH

CANCEL

SWITCH

SET/

COAST

SWITCH

HORN SWITCH

4

B68

HORN RELAY

STEERING ROLL
CONNECTOR

HORN

S1

F37

4

1 2 3

6

5

B68

4

1

2

3

5

3

2

1

3

2

1

RHD

RHD

LHD

LHD

CRUISE CONTROL
COMMAND SWITCH

F37

LHD

:

B144

RHD

:

F37

LHD

:

B144

RHD

:

1 2 3 4 5 6

9

7 8

10

12 13 14 15 16

22 23

11
24

17 18 19

21

20

CC-19

CRUISE CONTROL SYSTEM (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SYMPTOM

Step

Value

Yes

No

1

CHECK SET/COAST SWITCH CIRCUIT.
1) Turn ignition switch OFF.
2) Disconnect cruise control module harness

connector.

3) Measure voltage between harness connec-

tor terminal and chassis ground when SET/
COAST switch is pressed and not pressed.

Connector & terminal

(B94) No. 10 (+) — Chassis ground (

−−−−

):

Is the measured value less than the speci-
fied value, when SET/COAST switch is not
pressed?
Does the measured value exceed the spec-
ified value, when SET/COAST switch is
pressed?

When SET/COAST switch is
not pressed: 0 V, and when
SET/COAST switch is
pressed: 10 V

Go to step 2.

Go to step 4.

2

CHECK RESUME/ACCEL SWITCH CIRCUIT.
Measure voltage between harness connector
terminal and chassis ground when RESUME/
ACCEL switch is pressed and not pressed.

Connector & terminal

(B94) No. 9 (+) — Chassis ground (

−−−−

):

Is the measured value less than the specified
value, when RESUME/ACCEL switch is not
pressed?
Does the measured value exceed the specified
value, when RESUME/ACCEL switch is
pressed?

When RESUME/ACCEL
switch is not pressed: 0 V, and
when RESUME/ACCEL switch
is pressed: 10 V

Go to step 3.

Go to step 4.

3

CHECK CANCEL SWITCH CIRCUIT.
Measure voltage between harness connector
terminal and chassis ground when CANCEL
switch is pressed and not pressed.

Connector & terminal

(B94) No. 9 (+) — Chassis ground (

−−−−

):

(B94) No. 10 (+) — Chassis ground (

−−−−

):

Is the measured value less than the specified
value, when CANCEL switch is not pressed?
Does the measured value exceed the specified
value, when CANCEL switch is pressed?

When CANCEL switch is not
pressed: 0 V, and when CAN-
CEL switch is pressed: 10 V

Cruise control
command switch
circuit is OK.

Go to step 4.

4

CHECK POWER SUPPLY FOR COMMAND
SWITCH.
Check horn operation.
Does horn sound?

Horn sounds.

Go to step 5.

• Check fuse No.
6 (in main fuse
box).
• Check horn
relay. <Ref. to
COM-3, HORN
RELAY, INSPEC-
TION, Horn Sys-
tem.>
• Check harness
for open or short
between cruise
control command
switch and fuse &
relay box.

5

CHECK CRUISE CONTROL COMMAND
SWITCH.
Remove and check cruise control command
switch. <Ref. to CC-8, Cruise Control Com-
mand Switch.>
Is cruise control command switch OK?

Cruise control command
switch is OK.

Check harness
between cruise
control command
switch and cruise
control module.

Replace cruise
control command
switch.