Subaru Legacy III (2000-2003 year). Manual - part 577

AT-42

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

14.Diagnostic Procedure with Diagnostic Trouble Code (DTC)

A: DTC 11 ENGINE SPEED SIGNAL

DIAGNOSIS:
Engine speed input signal circuit is open or shorted.
TROUBLE SYMPTOM:
• No lock-up (after engine warm-up).
• POWER indicator light remains on when vehicle speed is “0”.
WIRING DIAGRAM:

AT-00775

9

30

H6T

H4N

17

ECM

B55

TCM

H4N

H6T

: EXCEPT 3.0L MODEL 
  AND TURBO MODEL

: 3.0L MODEL 
  AND TURBO MODEL

5 6 7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26

27 28

16 17 18 19

20 21

B135

B136

1 2

7

8 9

5

6

3

4

10 11 12
19 20 21

13 14 15 16

17 18

22 23 24

H6

:

H4

:

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

B136

B135 :

:

H4N

H6T

AT-43

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

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

ECM.

3) Measure resistance of harness between 

TCM and ECM connector.

Connector & terminal

Except 3.0 L model and TURBO model:

(B55) No. 17 — (B135) No. 30:

3.0 L model and TURBO model:

(B55) No. 17 — (B136) No. 9:

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

1 

Ω

Go to step 2.

Repair open circuit 
in harness 
between TCM and 
ECM connector.

2

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND ECM.
Measure resistance of harness between TCM 
connector and chassis ground.

Connector & terminal

(B55) No. 17 — Chassis ground:

Does the measured value exceed the specified 
value?

1 M

Ω

Go to step 3.

Repair short circuit 
in harness 
between TCM and 
ECM connector.

3

PREPARE SUBARU SELECT MONITOR.
Do you have a Subaru Select Monitor?

Subaru Select Monitor is avail-
able.

Go to step 5.

Go to step 4.

4

CHECK INPUT SIGNAL FOR TCM.
1) Connect connectors to TCM and ECM.
2) Turn ignition switch to ON (engine OFF).
3) Measure voltage between TCM connector 

and chassis ground.

Connector & terminal

(B55) No. 17 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10.5 V

Even if “POWER” 
indicator lights up, 
the circuit has 
returned to a nor-
mal condition at 
this time. A tempo-
rary poor contact 
of the connector or 
harness may be 
the cause. Repair 
harness or con-
nector in the TCM 
and ECM.

Go to step 6.

5

CHECK INPUT SIGNAL FOR TCM USING 
SUBARU SELECT MONITOR.
1) Connect connectors to TCM and ECM.
2) Connect Subaru Select Monitor to data link 

connector.

3) Start the engine, and turn Subaru Select 

Monitor switch to ON.

4) Warm-up the engine until engine coolant 

temperature is above 80

°

C (176

°

F).

5) Engine idling.
6) Read data of engine speed using Subaru 

Select Monitor.

•Display shows engine speed signal value sent 
from ECM.

Is the revolution value the same as the 
tachometer reading shown on the combina-
tion meter?

Tachometer and select monitor 
value are the same.

Even if “POWER” 
indicator lights up, 
the circuit has 
returned to a nor-
mal condition at 
this time. A tempo-
rary poor contact 
of the connector or 
harness may be 
the cause. Repair 
harness or con-
nector in the TCM 
and ECM.

Go to step 6.

6

CHECK POOR CONTACT.
Is there poor contact in engine speed signal 
circuit?

There is poor contact.

Repair poor con-
tact.

Go to step 7.

AT-44

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

7

CONFIRM DTC 11.
Replace ECM with a new one. Does the diag-
nostic trouble code (DTC) appear again, after 
the memory has been cleared?

DTC11 is displayed.

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

Replace ECM.

Step

Value

Yes

No

AT-45

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO: