Subaru Legacy III (2000-2003 year). Service manual — part 602

AT-142

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

61

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

range.

2) Measure voltage between TCM and chas-

sis ground.

Connector & terminal

(B55) No. 7 (+) — 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).>

62

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

combination meter.
Is “1” range indicator light bulb OK?

Bulb is normal.

Go to step 63.

Replace “1” range
indicator light bulb.
<Ref. to IDI-14,
Combination
Meter Assembly.>

63

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. 7 — (i11) No. 5:

3.0 L model and TURBO model:

(B55) No. 7 — (i10) No. 15:

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.

64

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. 7 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 65.

Repair ground
short circuit in “1”
range circuit.

65

CHECK POOR CONTACT.
Is there poor contact in inhibitor switch circuit?

There is poor contact.

Repair poor con-
tact.

Adjust inhibitor
switch and select
cable. <Ref. to AT-
50, ADJUST-
MENT, Inhibitor
Switch.> and
<Ref. to CS-12,
Select Cable.>

Step

Value

Yes

No

AT-143

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

AT-144

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

I:

CHECK HOLD SWITCH.

DIAGNOSIS:
• LED does not come on when hold switch is ON.
• Hold switch circuit is open or shorted.
TROUBLE SYMPTOM:
• 2nd gear is not held.
• Failure of vehicle to start in 2nd gear except 1st range.
WIRING DIAGRAM:

AT-00789

BATTERY

No.5

IGNITION

RELAY

B55

TCM

B133

SNOW

HOLD MODE

SWITCH

5

16

4

OFF

ON

E

E

i11

1 2 3 4

5 6 7

8 9 10 11 12 13 14 15 16

i12

1 2 3

4 5 6

7 8 9 10 11 12 13 14

B55

1 2 3 4

10 11 12
19 20 21

13

5 6

14 15

7

8

9

16

17

18

22

23

24

COMBINATION
METER

i10

A:

i11

B:

i12

C:

i1

B36

A12

H6

B5

C2

H4

C3

A8

N5

HOLD

H6

H4

: EXCEPT 3.0L MODEL AND TURBO MODEL

: 3.0L MODEL AND TURBO MODEL

H6

H6

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

i10

1 2 3 4 5 6 7

8 9 10 11 12 13 14

15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

B133

1

2

3 4 5 6

AT-145

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK HOLD SWITCH OPERATION.
When hold switch is turned OFF, does LED
light up?

LED lights up.

Go to step 5.

Go to step 2.

2

CHECK HOLD SWITCH OPERATION.
When hold switch is turned ON, does LED light
up?

LED lights up.

Go to step Inspec-
tion of SPORT
shift switch. <Ref.
to AT-148,
CHECK SPORT
SHIFT SWITCH.,
Diagnostic Proce-
dure for No-diag-
nostic Trouble
Code (DTC).>

Go to step 3.

3

CHECK HOLD INDICATOR LIGHT.
1) Turn ignition switch to OFF.
2) Remove combination meter.
3) Remove HOLD indicator light bulb from

combination meter.
Is HOLD indicator light bulb OK?

Bulb is normal.

Go to step 4.

Replace HOLD
indicator light bulb.
<Ref. to IDI-14,
Combination
Meter Assembly.>

4

CHECK HOLD SWITCH GROUND LINE.
1) Turn ignition switch to OFF.
2) Disconnect connector from hold switch.
3) Measure resistance of harness connector

between hold switch and chassis ground.

Connector & terminal

(B133) No. 4 — Chassis ground:

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

1

Ω

Go to step 5.

Repair open circuit
in harness
between hold
switch and chassis
ground.

5

CHECK HOLD SWITCH.
1) Hold switch turned ON.
2) Measure resistance between terminals of

hold switch.

Terminals

No. 4 — No. 5:

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

1

Ω

Go to step 6.

Repair hold
switch.

6

CHECK HOLD SWITCH.
1) Hold switch turned OFF.
2) Measure resistance between terminals of

hold switch.

Terminals

No. 4 — No. 5:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 7.

Repair hold
switch.

7

CHECK HARNESS CONNECTOR BETWEEN
TCM AND HOLD SWITCH.
1) Disconnect connector TCM and combina-

tion meter.

2) Measure resistance of harness connector

between TCM and hold switch.

Connector & terminal

(B55) No. 16 — (B133) No. 5:

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

1

Ω

Go to step 8.

Repair open circuit
in harness
between TCM and
hold switch con-
nector and poor
contact in cou-
pling connector.