Subaru Legacy 2002 Service Manual page 3327

Cruise Control System (Diagnostics)
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 (−):
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 (−):
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 (−):
4 CHECK POWER SUPPLY FOR COMMAND
SWITCH.
Check horn operation.
5 CHECK CRUISE CONTROL COMMAND
SWITCH.
Remove and check cruise control command
switch. <Ref. to CC-8, Cruise Control Com-
mand Switch.>
DIAGNOSTICS CHART WITH SYMPTOM
Step Check
Is the voltage 0 V when
SET/COAST switch is not
pressed? Is the voltage
more than 10 V when SET/
COAST switch is pressed?
Is the voltage 0 V when
RESUME/ACCEL switch is
not pressed? Is the voltage
more than 10 V when
RESUME/ACCEL switch is
pressed?
Is the voltage 0 V when
CANCEL switch is not
pressed? Is the voltage
more than 10 V when
CANCEL switch is
pressed?
Does horn sound?
Is cruise control command
switch OK?
CC-20
Yes
Go to step 2. Go to step 4.
Go to step 3. Go to step 4.
Cruise control Go to step 4.
command switch
circuit is OK.
¼ Check fuse No.
Go to step 5.
6 (in main fuse
box).
¼ Check horn
relay. <Ref. to
COM-4, HORN
RELAY,
INSPECTION,
Horn System.>
¼ Check harness
for open or short
between cruise
control command
switch and fuse &
relay box.
Check harness Replace cruise
between cruise control command
control command switch.
switch and cruise
control module.
No