SUBARU LEGACY 1996 Service Repair Manual

B2M0655
AS: DTC P0703
—BRAKE SWITCH INPUT MALFUNCTION
(ATBRK)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
10AS1Check operation of brake light.
10AS2Check harness between TCM and brake light
switch connector.
10AS3Check input signal for TCM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.

WIRING DIAGRAM:
OBD0587


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10. Diagnostics Chart with Trouble Code

10AS1
CHECK OPERATION OF BRAKE LIGHT.
: Does brake light come on when depressing
the brake pedal?
: Go to step10AS2.
: Repair or replace brake light circuit.
OBD0589A
10AS2CHECK HARNESS BETWEEN TCM AND
BRAKE LIGHT SWITCH CONNECTOR.
1) Disconnect connectors from TCM and brake light
switch.
2) Measure resistance of harness between TCM and
brake light switch connector.
: Connector & terminal
(B56) No. 7—(B64) No. 2:
(B56) No. 7—(B65) No. 3 (With cruise con-
trol):
(B56) No. 7—(B67) No. 2 (With traction
control):
Is the resistance less than 1Ω?
: Go to next step 3).
: Repair or replace harness and connector.
NOTE:
In this case, repair the following:

Open circuit in harness between TCM and brake light
switch connector

Poor contact in TCM connector

Poor contact in brake light switch connector
OBD0590A
3) Measure resistance of harness between TCM and
chassis ground.
: Connector & terminal
(B56) No. 7—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to step10AS3.
: Repair short circuit in harness between TCM and
brake light switch connector.
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10. Diagnostics Chart with Trouble Code

OBD0588A
10AS3
CHECK INPUT SIGNAL FOR TCM.
1) Connect connectors to TCM and brake light switch.
2) Measure voltage between TCM and chassis ground.
: Connector & terminal
(B56) No. 7 (+)—Chassis ground ():
Is the voltage less than 1 V when releasing
the brake pedal?
: Go to next.
: Adjust or replace brake light switch.
OBD0588A
: Connector & terminal
(B56) No. 7 (+)—Chassis ground ():
Is the voltage more than 10 V when
depressing the brake pedal?
: Go to next.
: Adjust or replace brake light switch.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Replace TCM.
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10. Diagnostics Chart with Trouble Code

B2M0656
AT: DTC P0705
—TRANSMISSION RANGE SENSOR CIRCUIT
MALFUNCTION (ATRNG)—
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Starter does not rotate when selector lever is in“P”or
“N”range.

Starter rotates when selector lever is in“R”,“D”,“3”,“2”
or“1”range.

Engine brake is not effected when selector lever is in“3”
range.

Shift characteristics are erroneous.
10AT1Check harness between TCM and inhibitor
switch connector.
10AT2Check inhibitor switch.
10AT3Check input signal for TCM.
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES.



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10. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:
B2M0767
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10. Diagnostics Chart with Trouble Code

OBD0596A
10AT1CHECK HARNESS BETWEEN TCM AND
INHIBITOR SWITCH CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM and transmission.
3) Measure resistance of harness between TCM and
transmission harness connector.
: Connector & terminal
(B56) No. 9—(B12) No. 3:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B56) No. 10—(B12) No. 2:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B56) No. 8—(B12) No. 1:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 1—(B12) No. 8:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 2—(B12) No. 7:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 3—(B12) No. 6:
Is the resistance less than 1Ω?
: Go to next.
: Repair open circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 4—(B12) No. 5:
Is the resistance less than 1Ω?
: Go to next step 4).
: Repair open circuit in harness between TCM and
transmission harness connector.
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10. Diagnostics Chart with Trouble Code

OBD0597A
4) Measure resistance of harness between TCM and
chassis ground.
: Connector & terminal
(B56) No. 9—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B56) No. 10—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B56) No. 8—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 1—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 2—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 3—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to next.
: Repair short circuit in harness between TCM and
transmission harness connector.
: Connector & terminal
(B54) No. 4—Chassis ground:
Is the resistance more than 1 MΩ?
: Go to step10AT2.
: Repair short circuit in harness between TCM and
transmission harness connector.
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10. Diagnostics Chart with Trouble Code

OBD0598A
10AT2
CHECK INHIBITOR SWITCH.
Measure resistance between transmission harness con-
nector receptacle’s terminals.
: Connector & terminal
(T3) No. 3—No. 4

Is the resistance less than 1Ωin“P”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
: Connector & terminal
(T3) No. 2—No. 4

Is the resistance less than 1Ωin“R”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
: Connector & terminal
(T3) No. 1—No. 4

Is the resistance less than 1Ωin“N”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
: Connector & terminal
(T3) No. 8—No. 4

Is the resistance less than 1Ωin“D”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
: Connector & terminal
(T3) No. 7—No. 4

Is the resistance less than 1Ωin“3”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
290
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10. Diagnostics Chart with Trouble Code

: Connector & terminal
(T3) No. 6—No. 4

Is the resistance less than 1Ωin“2”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to next.
:Goto.
: Connector & terminal
(T3) No. 5—No. 4

Is the resistance less than 1Ωin“1”
position?

Is the resistance more than 1 MΩin other
positions?
: Go to step10AT3.
:Goto.
: Is there faulty connection in the selector
cable?
: Repair connection of selector cable.
: Replace inhibitor switch.
OBD0595A
10AT3
CHECK INPUT SIGNAL FOR TCM.
1) Turn ignition switch to OFF.
2) Connect connector to TCM and transmission.
3) Turn ignition switch to ON.
4) Measure voltage between TCM and chassis ground.
: Connector & terminal
(B56) No. 9 (+)—Chassis ground ():

Is the voltage less than1Vin“P”and
“N”positions?

Is the voltage more than8Vinother
positions?
: Go to next.
:Goto.
: Connector & terminal
(B56) No. 10 (+)—Chassis ground ():

Is the voltage less than1Vin“R”posi-
tion?

Is the voltage more than6Vinother
positions?
: Go to next.
:Goto.
: Connector & terminal
(B56) No. 8 (+)—Chassis ground ():

Is the voltage less than1Vin“N”and
“P”positions?

Is the voltage more than8Vinother
positions?
: Go to next.
:Goto.
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10. Diagnostics Chart with Trouble Code

: Connector & terminal
(B54) No. 1 (+)—Chassis ground ():

Is the voltage less than1Vin“D”posi-
tion?

Is the voltage more than6Vinother
positions?
: Go to next.
:Goto.
: Connector & terminal
(B54) No. 2 (+)—Chassis ground ():

Is the voltage less than1Vin“3”posi-
tion?

Is the voltage more than6Vinother
positions?
: Go to next.
:Goto.
: Connector & terminal
(B54) No. 3 (+)—Chassis ground ():

Is the voltage less than1Vin“2”posi-
tion?

Is the voltage more than6Vinother
positions?
: Go to next.
:Goto.
: Connector & terminal
(B54) No. 4 (+)—Chassis ground ():

Is the voltage less than1Vin“1”posi-
tion?

Is the voltage more than6Vinother
positions?
: Repair poor contact in TCM connector.
:Goto.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Replace TCM.
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10. Diagnostics Chart with Trouble Code