Subaru Legacy (2005 year). Manual — part 548

4AT(diag)-29

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure for Subaru Select Monitor Communication

CHECK INSTALLATION OF TRANSMISSION
HARNESS CONNECTOR.

Is the transmission harness
connector connected to bulk-
head harness connector?

Go to step 11.

Connect the bulk-
head harness con-
nector to
transmission har-
ness connector.

CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in control

module power supply and data
link connector?

Repair the poor
contact.

Go to step 12.

CHECK POWER SUPPLY OF TCM.
1) Disconnect the connector from TCM.
2) Turn the ignition switch to ON.
3) Measure the voltage between TCM con-
nector and chassis ground.

Connector & terminal

(B55) No. 27 (+) — Chassis ground (

−

(B55) No. 28 (+) — Chassis ground (

−

(B55) No. 29 (+) — Chassis ground (

−

Is the voltage 10 — 13 V?

Go to step 14.

Go to step 13.

CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse M/B (No. 12).

Is the fuse M/B (No. 12) blown
out?

Replace the fuse
M/B (No. 12). If the
replaced fuse M/B
(No. 12) has blown
out easily, repair
the short circuit of
harness between
fuse M/B (No. 12)
and TCM.

Repair the open
circuit of harness
between fuse M/B
(No. 12) and TCM,
or fuse M/B (No.
12) and battery,
and poor contact
in connector.

CHECK IGNITION POWER SUPPLY CIR-
CUIT.
1) Turn the ignition switch to ON (engine
OFF).
2) Measure the ignition power supply voltage
between TCM connector and chassis ground.

Connector & terminal

(B55) No. 21 (+) — Chassis ground (

−

(B55) No. 31 (+) — Chassis ground (

−

Is the voltage 10 — 13 V?

Go to step 16.

Go to step 15.

CHECK FUSE.
Remove the fuse F/B (No. 12).

Is the fuse F/B (No. 12) blown
out?

Replace the fuse
F/B (No. 12). If the
replaced fuse F/B
(No. 12) has blown
out easily, repair
the short circuit of
harness between
fuse F/B (No. 12)
and TCM.

Repair the open
circuit of harness
between fuse F/B
(No. 12) and TCM,
or fuse F/B (No.
12) and battery,
and poor contact
in connector.

CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and
transmission.
3) Measure the resistance of harness
between TCM and transmission connector.

Connector & terminal

(B54) No. 8 — (B11) No. 19:
(B54) No. 17 — (B11) No. 19:
(B55) No. 2 — (B11) No. 20:
(B55) No. 3 — (B11) No. 20:

Is the resistance less than 1
Ω?

Go to step 17.

Repair the open
circuit of harness
between TCM and
transmission har-
ness connector,
and poor contact
in connector.

Step

Check

Yes

4AT(diag)-30

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure for Subaru Select Monitor Communication

CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND TRANSMISSION
GROUND.
Measure the resistance of harness between
transmission and transmission ground.

Connector & terminal

(T4) No. 19 — Transmission ground:
(T4) No. 20 — Transmission ground:

Is the resistance less than 1
Ω?

Go to step 18.

Repair the open
circuit of harness
between transmis-
sion and transmis-
sion ground.

CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in TCM

power supply, ground and data
link connector?

Repair the con-
nector.

Replace the TCM.
<Ref. to 4AT-66,
Transmission Con-
trol Module
(TCM).>

Step

Check

Yes

4AT(diag)-31

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

List of Diagnostic Trouble Code (DTC)

12.List of Diagnostic Trouble Code (DTC)

A: LIST

DTC

Item

Contents of diagnosis

Reference target

P0705

Transmission Range
Sensor Circuit (PRNDL
Input)

Inhibitor switch malfunction short
circuit

<Ref. to 4AT(diag)-33, DTC P0705 TRANS-
MISSION RANGE SENSOR CIRCUIT (PRNDL
INPUT), Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0712

Transmission Fluid Tem-
perature Sensor Circuit
Low Input

ATF temperature sensor is faulty
or input signal circuit is open.

<Ref. to 4AT(diag)-41, DTC P0712 TRANS-
MISSION FLUID TEMPERATURE SENSOR
CIRCUIT LOW INPUT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0713

Transmission Fluid Tem-
perature Sensor Circuit
High Input

ATF temperature sensor is faulty
or input signal circuit is shorted.

<Ref. to 4AT(diag)-44, DTC P0713 TRANS-
MISSION FLUID TEMPERATURE SENSOR
CIRCUIT HIGH INPUT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0715

Input/Turbine Speed
Sensor Circuit

Torque converter turbine speed
sensor malfunction, short input
signal circuit

<Ref. to 4AT(diag)-47, DTC P0715 INPUT/
TURBINE SPEED SENSOR CIRCUIT, Diag-
nostic Procedure with Diagnostic Trouble Code
(DTC).>

P0719

Torque Converter/Brake
Switch “B” Circuit Low

Brake switch malfunction, open
input signal circuit

<Ref. to 4AT(diag)-49, DTC P0719 TORQUE
CONVERTER/BRAKE SWITCH “B” CIRCUIT
LOW, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0720

Output Speed Sensor
Circuit

Front vehicle speed sensor mal-
function, open or short input sig-
nal circuit

<Ref. to 4AT(diag)-53, DTC P0720 OUTPUT
SPEED SENSOR CIRCUIT, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P0724

Torque Converter/Brake
Switch “B” Circuit High

Brake switch malfunction, short
input signal circuit

<Ref. to 4AT(diag)-56, DTC P0724 TORQUE
CONVERTER/BRAKE SWITCH “B” CIRCUIT
HIGH, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0725

Engine Speed Input Cir-
cuit

Open or short engine speed out-
put signal circuit

<Ref. to 4AT(diag)-59, DTC P0725 ENGINE
SPEED INPUT CIRCUIT, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P0731

Gear 1 Incorrect Ratio