Subaru Legacy III (2000-2003 year). Manual — part 601

AT-138

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

41

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM and

inhibitor switch.

3) Measure resistance of harness between

TCM and inhibitor switch connector.

Connector & terminal

(B55) No. 4 — (T7) No. 3:

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

1

Ω

Go to step 42.

Repair open circuit
in harness
between TCM and
inhibitor switch
connector, and
poor contact in
coupling connec-
tor.

42

CHECK INPUT SIGNAL FOR TCM.
1) Turn ignition switch to OFF.
2) Connect connector to TCM and inhibitor

switch.

3) Turn ignition switch to ON.
4) Move select lever to D range.
5) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 4 (+) — Chassis ground (–):

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

1 V

Go to step 43.

Go to step 65.

43

CHECK INPUT SIGNAL FOR TCM.
1) Position select lever to any other than D

range.

2) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 4 (+) — Chassis ground (–):

Does the measured value exceed the spec-
ified value?

8 V

Go to step 65.

Replace TCM.
<Ref. to AT-76,
Transmission Con-
trol Module
(TCM).>

44

CHECK “D” RANGE INDICATOR LIGHT
BULB.
1) Turn ignition switch to OFF.
2) Remove combination meter.
3) Remove “D” range indicator light bulb from

combination meter.
Is “D” range indicator light bulb OK?

Bulb is normal.

Go to step 45.

Replace “D” range
indicator light bulb.
<Ref. to IDI-14,
Combination
Meter Assembly.>

45

CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect connectors from TCM and com-

bination meter.

2) Measure resistance of harness between

TCM and combination meter.

Connector & terminal

Except 3.0 L model and TURBO model:

(B55) No. 4 — (i11) No. 4:

3.0 L model and TURBO model:

(B55) No. 4 — (i10) No. 20:

Does the measured value exceed the spec-
ified value?

1

Ω

Go to step 65.

Repair open circuit
in harness
between inhibitor
switch connector
and combination
meter.

Step

Value

Yes

No

AT-139

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

46

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM, inhibitor

switch and combination meter.

3) Measure resistance of harness between

TCM and chassis ground.

Connector & terminal

(B55) No. 4 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 47.

Repair ground
short circuit in “D”
range circuit.

47

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connector from TCM and inhibi-

tor switch.

3) Measure resistance of harness between

TCM and inhibitor switch connector.

Connector & terminal

(B55) No. 5 — (B12) No. 7:

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

1

Ω

Go to step 48.

Repair open circuit
in harness
between TCM and
inhibitor switch
connector, and
poor contact in
coupling connec-
tor.

48

CHECK INPUT SIGNAL FOR TCM.
1) Turn ignition switch to OFF.
2) Connect connector to TCM and inhibitor

switch.

3) Turn ignition switch to ON.
4) Move select lever to 3 range.
5) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 5 (+) — Chassis ground (–):

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

1 V

Go to step 49.

Go to step 65.

49

CHECK INPUT SIGNAL FOR TCM.
1) Position select lever to any other than 3

range.

2) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 5 (+) — Chassis ground (–):

Does the measured value exceed the spec-
ified value?

8 V

Go to step 65.

Replace TCM.
<Ref. to AT-76,
Transmission Con-
trol Module
(TCM).>

50

CHECK “3” RANGE INDICATOR LIGHT
BULB.
1) Turn ignition switch to OFF.
2) Remove combination meter.
3) Remove “3” range indicator light bulb from

combination meter.
Is “3” range indicator light bulb OK?

Bulb is normal.

Go to step 51.

Replace “3” range
indicator light bulb.
<Ref. to IDI-14,
Combination
Meter Assembly.>

Step

Value

Yes

No

AT-140

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

51

CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect connectors from TCM and com-

bination meter.

2) Measure resistance of harness between

TCM and combination meter.

Connector & terminal

Except 3.0 L model and TURBO model:

(B55) No. 5 — (i11) No. 11:

3.0 L model and TURBO model:

(B55) No. 5 — (i10) No. 19:

Does the measured value exceed the spec-
ified value?

1

Ω

Go to step 65.

Repair open circuit
in harness
between TCM
connector and
combination
meter, and poor
contact in TCM
connector.

52

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM, inhibitor

switch and combination meter.

3) Measure resistance of harness between

TCM and chassis ground.

Connector & terminal

(B55) No. 5 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 53.

Repair ground
short circuit in “3”
range circuit.

53

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connector from TCM and inhibi-

tor switch.

3) Measure resistance of harness between

TCM and inhibitor switch connector.

Connector & terminal

(B55) No. 6 — (T7) No. 4:

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

1

Ω

Go to step 54.

Repair open circuit
in harness
between TCM and
inhibitor switch
connector, and
poor contact in
coupling connec-
tor.

54

CHECK INPUT SIGNAL FOR TCM.
1) Turn ignition switch to OFF.
2) Connect connector to TCM and inhibitor

switch.

3) Turn ignition switch to ON.
4) Move select lever to 2 range.
5) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 6 (+) — Chassis ground (–):

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

1 V

Go to step 55.

Go to step 65.

55

CHECK INPUT SIGNAL FOR TCM.
1) Position select lever to any other than 2

range.

2) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 6 (+) — Chassis ground (–):

Does the measured value exceed the spec-
ified value?

8 V

Go to step 65.

Replace TCM.
<Ref. to AT-76,
Transmission Con-
trol Module
(TCM).>

Step

Value

Yes

No

AT-141

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

56

CHECK “2” RANGE INDICATOR LIGHT
BULB.
1) Turn ignition switch to OFF.
2) Remove combination meter.
3) Remove “2” range indicator light bulb from

combination meter.
Is “2” range indicator light bulb OK?

Bulb is normal.

Go to step 57.

Replace “2” range
indicator light bulb.
<Ref. to IDI-14,
Combination
Meter Assembly.>

57

CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect connectors from TCM and com-

bination meter.

2) Measure resistance of harness between

TCM and combination meter.

Connector & terminal

Except 3.0 L model and TURBO model:

(B55) No. 6 — (i11) No. 12:

3.0 L model and TURBO model:

(B55) No. 6 — (i10) No. 16:

Does the measured value exceed the spec-
ified value?

1

Ω

Go to step 65.

Repair open circuit
in harness
between TCM and
combination
meter, and poor
contact in TCM
connector.

58

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM, inhibitor

switch and combination meter.

3) Measure resistance of harness between

TCM and chassis ground.

Connector & terminal

(B55) No. 6 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 59.

Repair ground
short circuit in “2”
range circuit.

59

CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn ignition switch to OFF.
2) Disconnect connectors from TCM and

inhibitor switch.

3) Measure resistance of harness between

TCM and inhibitor switch connector.

Connector & terminal

(B55) No. 7 — (T7) No. 6:

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

1

Ω

Go to step 60.

Repair open circuit
in harness
between TCM and
inhibitor switch
connector, and
poor contact in
coupling connec-
tor.

60

CHECK INPUT SIGNAL FOR TCM.
1) Turn ignition switch to OFF.
2) Connect connector to TCM and inhibitor

switch.

3) Turn ignition switch to ON.
4) Move select lever to 1 range.
5) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 7 (+) — Chassis ground (–):

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

1 V

Go to step 61.

Go to step 65.

Step

Value

Yes

No