Subaru Legacy III (2000-2003 year). Manual - part 163

EN(H4SO)-264

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

7

CHECK POOR CONTACT.
Check poor contact in transmission harness 
connector.
Is there poor contact in transmission harness 
connector?

There is poor contact.

Repair poor con-
tact in transmis-
sion harness 
connector.

Contact SUBARU 
distributor service.

NOTE:
Inspection by DTM
is required, be-
cause probable
cause is deteriora-
tion of multiple
parts.

Step

Value

Yes

No

EN(H4SO)-265

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

EN(H4SO)-266

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BP:DTC P0864 — TCM COMMUNICATION CIRCUIT RANGE/PERFORMANCE —

• DTC DETECTING CONDITION:

• Two consecutive driving cycles with fault

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode<Ref. to EN(H4SO)-47, OPER-
ATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO)-40, OPERATION, Inspection 
Mode.> .
• WIRING DIAGRAM:

EN-01138

19

21

B137 ECM

TCM

B56

B137

4

1
5

3

2
6

18

15

16

7 8 9 10 11

17

19 20

12 13

14

B56

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

EN(H4SO)-267

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK DRIVING CONDITION.
1) Start and warm-up the engine until the radi-

ator fan makes one complete rotation.

2) Drive the vehicle.

Is AT shift control functioning properly?

Operates properly.

Go to step 2.

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

2

CHECK ACCESSORY.
Are car phone and/or CB installed on vehicle?

Installed.

Repair grounding 
line of car phone 
or CB system.

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