CC(H4DOTC 2.5)-17
CRUISE CONTROL SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK CRUISE CONTROL MAIN SWITCH
CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the ECM harness connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between harness con-
nector terminal and chassis ground when the
main switch is pressed and is not pressed.
Connector & terminal
(B136) No. 7 (+) — Chassis ground (
−):Is the voltage 0 V when the
main switch is not pressed? Is
the voltage more than 10 V
when the main switch is
pressed?Go to step 2. Check the fuse
No. 18 (in fuse &
relay box).
Check the har-
ness for open or
short between
cruise control
command switch
and fuse & relay
box. If no malfunc-
tion is found after
checking above,
Go to step 6.
2 CHECK SET/COAST SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the ECM harness connector.
3) Measure the voltage between harness con-
nector terminal and chassis ground when SET/
COAST switch is pressed and not pressed.
Connector & terminal
(B136) No. 11 (+) — Chassis ground (
−):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?Go to step 3.Go to step 5.
3 CHECK RESUME/ACCEL SWITCH CIRCUIT.
Measure the voltage between harness connec-
tor terminal and chassis ground when
RESUME/ACCEL switch is pressed and not
pressed.
Connector & terminal
(B136) No. 10 (+) — Chassis ground (
−):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?Go to step 4.Go to step 5.
4 CHECK CANCEL SWITCH CIRCUIT.
Measure the voltage between harness connec-
tor terminal and chassis ground when CAN-
CEL switch is pressed and not pressed.
Connector & terminal
(B136) No. 10 (+) — Chassis ground (
−):
(B136) No. 11 (+) — Chassis ground (
−): Is the voltage 0 V when CAN-
CEL switch is not pressed? Is
the voltage more than 10 V
when CANCEL switch is
pressed?Cruise control
command switch
circuit is OK.Go to step 5.
5 CHECK POWER SUPPLY FOR COMMAND
SWITCH.
Check the horn operation.Does the horn sound? Go to step 6. Check the fuse
No. 6 (in main fuse
box).
Check the horn
relay.
RELAY, INSPEC-
TION, Horn Sys-
tem.>
Check the har-
ness for open or
short between
cruise control
command switch
and fuse & relay
box.
6 CHECK CRUISE CONTROL COMMAND
SWITCH.
Remove and check the cruise control com-
mand switch.
switch OK?Check the harness
between cruise
control command
switch and ECM.Replace the cruise
control command
switch.
CC(H4DOTC 2.5)-19
CRUISE CONTROL SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK STOP LIGHT SWITCH AND BRAKE
SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the stop light switch and brake
switch harness connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between harness con-
nector terminal and chassis ground.
Connector & terminal
(B65) No. 2 (+) — Chassis ground (
−): Is the voltage more than 10 V? Go to step 2. Check the fuse
No. 16 (in fuse &
relay box).
Check the har-
ness for open or
short between
stop light/brake
switch and fuse &
relay box.
2 CHECK STOP LIGHT SWITCH AND BRAKE
SWITCH CIRCUIT.
Measure the voltage between harness connec-
tor terminal and chassis ground.
Connector & terminal
(B65) No. 1 (+) — Chassis ground (
−): Is the voltage more than 10 V? Go to step 3. Check the fuse
No. 11 (in fuse &
relay box).
Check the har-
ness for open or
short between
stop light/brake
switch and fuse &
relay box.
Check the clutch
switch and circuit.
3 CHECK STOP LIGHT SWITCH AND BRAKE
SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the ECM harness connector.
3) Measure the resistance between ECM har-
ness connector terminal and stop light switch
and brake switch harness connector terminal.
Connector & terminal
(B136) No. 8 — (B65) No. 3:
(B136) No. 9 — (B65) No. 4: Is the resistance less than 10
Ω? Go to step 4.Repair the har-
ness.
4 CHECK STOP LIGHT SWITCH AND BRAKE
SWITCH.
Remove and check the stop light switch and
brake switch.
brake switch OK? Stop light switch
and brake switch
circuit are OK.Replace the stop
light switch and
brake switch.
CC(H4DOTC 2.5)-21
CRUISE CONTROL SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK CLUTCH SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the clutch switch harness con-
nector.
3) Turn the ignition switch to ON.
4) Measure the voltage between harness con-
nector terminal and chassis ground.
Connector & terminal
(B107) No. 2 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 2. Check the fuse
No. 11 (fuse &
relay box).
Check the har-
ness for open or
short between
clutch switch and
fuse & relay box.
2 CHECK CLUTCH SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the ECM harness connector.
3) Measure the resistance between clutch
switch harness connector terminal and ECM
harness connector terminal.
Connector & terminal
(B107) No. 1 — (B134) No. 1:Is the resistance less than 10
Ω? Go to step 3.Repair the har-
ness.
3 CHECK CLUTCH SWITCH.
Remove and check the clutch switch.
cuit is OK.Replace the clutch
switch.
CC(H4DOTC 2.5)-25
CRUISE CONTROL SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK IGNITION SWITCH CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the ECM harness connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between harness con-
nector terminal and chassis ground.
Connector & terminal
(B137) No. 14 (+) — Chassis ground (
−): Is the voltage more than 10 V? Check the poor
contact of ECM
connector. Check the fuse
No. 11 (fuse &
relay box).
Check the har-
ness for open or
short between
ignition switch and
ECM.
EN(H4SO)-202
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Connect the test mode connector at the
lower portion of instrument panel (on the
driver’s side).
3) Turn the ignition switch to ON.
4) While operating the radiator fan relay, mea-
sure the voltage between ECM and chassis
ground.
N
OTE:
Radiator fan relay operation can be executed
using Subaru Select Monitor. For procedure,
refer to “Compulsory Valve Operation Check
Mode”.
Connector & terminal
(B134) No. 14 (+) — Chassis ground (
−):Is the voltage 0 — 10 V? Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK GROUND SHORT CIRCUIT IN RADI-
ATOR MAIN FAN RELAY CONTROL CIR-
CUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance of harness
between ECM connector and chassis ground.
Connector & terminal
(B134) No. 14 — Chassis ground:Is the resistance less than 10
Ω?Repair the ground
short circuit in
radiator main fan
relay control cir-
cuit.Go to step 3.
3 CHECK POWER SUPPLY FOR RELAY.
1) Remove the main fan relay from A/C relay
holder.
2) Turn the ignition switch to ON.
3) Measure the voltage between fuse and
relay box (F/B) connector and chassis ground.
Connector & terminal
(F27) No. 34 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 4.Repair open circuit
in harness
between ignition
switch and fuse
and relay box (F/B)
connector.
4 CHECK MAIN FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between main fan
relay terminals.
Te r m i n a l s
No. 32 — No. 34:Is the resistance 87 — 107 Ω? Go to step 5.Replace the main
fan relay.
5 CHECK OPEN CIRCUIT IN MAIN FAN RE-
LAY CONTROL CIRCUIT.
Measure the resistance of harness between
ECM and main fan relay connector.
Connector & terminal
(B134) No. 14 — (F27) No. 32:Is the resistance less than 1
Ω?Go to step 6.Repair harness
and connector.
NOTE:
In this case repair
the following:
Open circuit in
harness between
ECM and main fan
relay connector
Poor contact in
coupling connector
6 CHECK POOR CONTACT.
Check poor contact in ECM or main fan relay
connector. Is there poor contact in ECM or
main fan relay connector?Repair the poor
contact in ECM or
main fan relay con-
nector.Contact the SUB-
ARU dealer.
EN(H4SO)-246
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK INPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B134) No. 9 (+) — Chassis ground (
−):Is the voltage more than 10 V? Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and chassis ground.
Connector & terminal
(B135) No. 9 — Chassis ground:Is the resistance less than 10
Ω?Repair ground
short circuit in har-
ness between
ECM connector
and battery termi-
nal.Go to step 3.
3 CHECK FUSE SBF-5.Is the fuse blown out? Replace the fuse. Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and battery
Poor contact in
ECM connector.
Poor contact in
battery terminal
EN(H4DOTC)-234
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Connect the test mode connector.
3) Turn the ignition switch to ON.
4) While operating the radiator fan relay, mea-
sure voltage between ECM terminal and
ground.
N
OTE:
Radiator fan relay operation can be executed
using Subaru Select Monitor.For procedure, re-
fer to “Compulsory Valve Operation Check
Mode”.
Connector & terminal
(B135) No. 24 (+) — Chassis ground (
−):
(B135) No. 25 (+) — Chassis ground (
−):Does the voltage vary between
0 — 10 V?Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK GROUND SHORT CIRCUIT IN RADI-
ATOR FAN RELAY CONTROL CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance of harness
between ECM connector and chassis ground.
Connector & terminal
(B135) No. 24 — Chassis ground:
(B135) No. 25 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair ground
short circuit in
radiator fan relay
control circuit.
3 CHECK POWER SUPPLY FOR RELAY.
1) Remove the main fan relay 1 and sub fan
relay from A/C relay holder.
2) Turn the ignition switch to ON.
3) Measure the voltage between fuse and
relay box (F/B) connector and chassis ground.
Connector & terminal
(F27) No. 25 (+) — Chassis ground (
−):
(F27) No. 34 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 4.Repair open circuit
in harness
between ignition
switch and fuse
and relay box (F/B)
connector.
4 CHECK MAIN FAN RELAY 1.
1) Turn the ignition switch to OFF.
2) Measure the resistance of main fan relay 1
terminals.
Te r m i n a l s
No. 32 — No. 34:Is the resistance 87 — 107 Ω? Go to step 5.Replace the main
fan relay 1.
5 CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between sub fan
relay terminals.
Te r m i n a l s
No. 25 — No. 27:Is the resistance 87 — 107 Ω? Go to step 6.Replace the sub
fan relay.
6 CHECK OPEN CIRCUIT IN FAN RELAY
CONTROL CIRCUIT.
Measure the resistance of harness between
ECM and fan relay connector.
Connector & terminal
(B135) No. 24 — (F27) No. 27:
(B135) No. 25 — (F27) No. 32:Is the resistance less than 1
Ω?Go to step 7.Repair harness
and connector.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and fan relay
connector
Poor contact in
coupling connector
EN(H4DOTC)-286
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK INPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B135) No. 19 (+) — Chassis ground (
−):Is the voltage more than 10 V? Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and chassis ground.
Connector & terminal
(B135) No. 19 — Chassis ground:Is the resistance less than 10
Ω?Repair ground
short circuit in har-
ness between
ECM connector
and battery termi-
nal.Go to step 3.
3 CHECK FUSE SBF-5.Is the fuse blown out? Replace the fuse. Repair the har-
ness and connec-
tor.
N
OTE:
In this case repair
the following:
Open circuit in
harness between
ECM and battery
Poor contact in
ECM connector.
Poor contact in
battery terminal