Subaru Legacy IV (2008 year). Service manual — part 754

5AT(diag)-31

Diagnostic Procedure for Subaru Select Monitor Communication

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

10

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.

11

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.

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 connec-
tor and chassis ground.

Connector & terminal

(B55) No. 24 (+) — Chassis ground (–):
(B55) No. 25 (+) — Chassis ground (–):
(B55) No. 26 (+) — Chassis ground (–):

Is the voltage 10 — 13 V?

Go to step 15.

Go to step 13.

13

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

Is the fuse (No. 12) blown out? Replace the fuse

(No. 12).

Go to step 14.

14

CHECK HARNESS.
Measure the resistance between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 24 — Chassis ground:
(B55) No. 25 — Chassis ground:
(B55) No. 26 — Chassis ground:

Is the resistance 10

: or less? Replace the fuse

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

Go to step 15.

15

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. 17 (+) — Chassis ground (–):

Is the voltage 10 — 13 V?

Go to step 17.

Go to step 16.

16

CHECK FUSE (NO. 21).
Remove the fuse (No. 21).

Is the fuse (No. 21) blown out? Replace the fuse

(No. 21). If the
replaced fuse (No.
21) has blown out
easily, repair short
circuit of harness
between fuse (No.
21) and TCM.

Go to step 17.

17

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

Connector & terminal

(B55) No. 22 — Transmission ground:
(B55) No. 23 — Transmission ground:

Is the resistance 1 M

: or

more?

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

Go to step 18.

18

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

power supply, ground and data
link connector?

Repair the connec-
tor.

Replace the TCM.
<Ref. to 5AT-60,
Transmission Con-
trol Module
(TCM).>

Step

Check

Yes

No

5AT(diag)-32

List of Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

13.List of Diagnostic Trouble Code (DTC)

A: LIST

DTC

Item

Contents of diagnosis

Reference

P0705

Transmission Range
Sensor Circuit (PRNDL
Input)

Inhibitor switch malfunction, open
or short circuit

<Ref. to 5AT(diag)-35, 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 1 mal-
function, or open input signal cir-
cuit

<Ref. to 5AT(diag)-39, 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 1 mal-
function, short input signal circuit

<Ref. to 5AT(diag)-41, DTC P0713 TRANS-
MISSION FLUID TEMPERATURE SENSOR
CIRCUIT HIGH INPUT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0715

Input/Turbine Speed
Sensor Circuit

Turbine speed sensor 1 malfunc-
tion, short input signal circuit

<Ref. to 5AT(diag)-43, DTC P0715 INPUT/
TURBINE SPEED SENSOR CIRCUIT, Diag-
nostic Procedure with Diagnostic Trouble Code
(DTC).>

P0719

Brake Switch Circuit Low

Brake switch malfunction, open
input signal circuit, body inte-
grated unit malfunction, CAN
communication failure

<Ref. to 5AT(diag)-46, DTC P0719 BRAKE
SWITCH CIRCUIT LOW, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0720

Output Speed Sensor
Circuit

Front wheel speed sensor is
faulty or input signal circuit,
ground, power supply is open or
shorted.

<Ref. to 5AT(diag)-48, DTC P0720 OUTPUT
SPEED SENSOR CIRCUIT, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P0724

Brake Switch Circuit
High

Brake switch malfunction, short
circuit of input signal, body inte-
grated unit, CAN communication
failure

<Ref. to 5AT(diag)-51, DTC P0724 BRAKE
SWITCH CIRCUIT HIGH, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P0731

Gear 1 Incorrect Ratio

Vehicle sensor, turbine speed
sensor, control valve malfunction
or shift clutch malfunction

<Ref. to 5AT(diag)-53, DTC P0731 GEAR 1
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0732

Gear 2 Incorrect Ratio

Vehicle sensor, turbine speed
sensor, control valve malfunction
or shift clutch malfunction

<Ref. to 5AT(diag)-53, DTC P0732 GEAR 2
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0733

Gear 3 Incorrect Ratio

Vehicle sensor, turbine speed
sensor or shift clutch malfunction

<Ref. to 5AT(diag)-53, DTC P0733 GEAR 3
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0734

Gear 4 Incorrect Ratio

Vehicle sensor, turbine speed
sensor or shift clutch malfunction

<Ref. to 5AT(diag)-53, DTC P0734 GEAR 4
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0735

Gear 5 Incorrect Ratio

Vehicle sensor, turbine speed
sensor or shift clutch malfunction

<Ref. to 5AT(diag)-53, DTC P0735 GEAR 5
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0736

Reverse Incorrect Ratio

Vehicle sensor, turbine speed
sensor or shift clutch malfunction

<Ref. to 5AT(diag)-54, DTC P0736 REVERSE
INCORRECT RATIO, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P0741

Torque Converter Clutch
Circuit Performance or
Stuck Off

Lock-up clutch is faulty or valve is
stuck.

<Ref. to 5AT(diag)-55, DTC P0741 TORQUE
CONVERTER CLUTCH CIRCUIT PERFOR-
MANCE OR STUCK OFF, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P0743

Torque Converter Clutch
Circuit Electrical

L/U solenoid circuit malfunction
or L/U solenoid body malfunction

<Ref. to 5AT(diag)-57, DTC P0743 TORQUE
CONVERTER CLUTCH CIRCUIT ELECTRI-
CAL, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

5AT(diag)-33

List of Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

P0748

Pressure Control Sole-
noid “A” Electrical

Line pressure solenoid circuit
malfunction or line pressure sole-
noid body malfunction

<Ref. to 5AT(diag)-59, DTC P0748 PRES-
SURE CONTROL SOLENOID “A” ELECTRI-
CAL, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0751

Shift Solenoid “A” Perfor-
mance or Stuck Off

Fr/B Solenoid Function Malfunc-
tion

<Ref. to 5AT(diag)-61, DTC P0751 SHIFT
SOLENOID “A” PERFORMANCE OR STUCK
OFF, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0753

Shift Solenoid “A” Elec-
trical

Fr/B solenoid circuit malfunction
or Fr/B solenoid body malfunction

<Ref. to 5AT(diag)-63, DTC P0753 SHIFT
SOLENOID “A” ELECTRICAL, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0756

Shift Solenoid “B” Perfor-
mance or Stuck Off

Shift Solenoid “B” Performance
malfunction

<Ref. to 5AT(diag)-65, DTC P0756 SHIFT
SOLENOID “B” PERFORMANCE OR STUCK
OFF, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0758

Shift Solenoid “B” Elec-
trical

I/C solenoid circuit malfunction or
I/C solenoid body malfunction

<Ref. to 5AT(diag)-67, DTC P0758 SHIFT
SOLENOID “B” ELECTRICAL, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0761

Shift Solenoid “C” Perfor-
mance or Stuck Off

H&LR/C solenoid malfunction

<Ref. to 5AT(diag)-69, DTC P0761 SHIFT
SOLENOID “C” PERFORMANCE OR STUCK
OFF, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0763

Shift Solenoid “C” Elec-
trical

H&LR/C solenoid circuit malfunc-
tion or H&LR/C solenoid body
malfunction

<Ref. to 5AT(diag)-71, DTC P0763 SHIFT
SOLENOID “C” ELECTRICAL, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0766

Shift Solenoid “D” Perfor-
mance or Stuck Off

D/C solenoid malfunction

<Ref. to 5AT(diag)-73, DTC P0766 SHIFT
SOLENOID “D” PERFORMANCE OR STUCK
OFF, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0768

Shift Solenoid “D” Elec-
trical

D/C solenoid circuit malfunction
or D/C solenoid body malfunction

<Ref. to 5AT(diag)-75, DTC P0768 SHIFT
SOLENOID “D” ELECTRICAL, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0771

Shift Solenoid “E” Perfor-
mance or Stuck Off

Fwd/B solenoid malfunction

<Ref. to 5AT(diag)-77, DTC P0771 SHIFT
SOLENOID “E” PERFORMANCE OR STUCK
OFF, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>

P0773

Shift Solenoid “E” Elec-
trical

Fwd/B solenoid circuit malfunc-
tion or Fwd/B solenoid body mal-
function

<Ref. to 5AT(diag)-79, DTC P0773 SHIFT
SOLENOID “E” ELECTRICAL, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0801

Reverse Inhibit Control
Circuit

• Shift lock solenoid is faulty or
output signal circuit is open or
shorted.
• Blown out of TCM+B fuse

<Ref. to 5AT(diag)-81, DTC P0801 REVERSE
INHIBIT CONTROL CIRCUIT, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0817

Starter Disable Circuit

• PN signal output circuit is open
or shorted.
• ECM Source Voltage Is Abnor-
mal
• Blown out of TCM+B fuse

<Ref. to 5AT(diag)-83, DTC P0817 STARTER
DISABLE CIRCUIT, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>

P0957

Backup Light Relay Cir-
cuit Low

Back-up relay output circuit is
open, shorted or relay OFF mal-
function

<Ref. to 5AT(diag)-85, DTC P0957 BACKUP
LIGHT RELAY CIRCUIT LOW, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P0958

Backup Light Relay Cir-
cuit High

Back-up relay output circuit is
open, shorted or relay ON mal-
function

<Ref. to 5AT(diag)-87, DTC P0958 BACKUP
LIGHT RELAY CIRCUIT HIGH, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P1706

AT Vehicle Speed Sen-
sor Circuit Malfunction
(Rear Wheel)

Rear wheel speed sensor is faulty
or input circuit, ground, power
supply is open or shorted.

<Ref. to 5AT(diag)-89, DTC P1706 AT VEHI-
CLE SPEED SENSOR CIRCUIT MALFUNC-
TION (REAR WHEEL), Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

DTC

Item

Contents of diagnosis

Reference

5AT(diag)-34

List of Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

P1707

AT AWD Solenoid Valve
Circuit Malfunction

AWD solenoid circuit malfunction
or AWD solenoid body malfunc-
tion

<Ref. to 5AT(diag)-91, DTC P1707 AT AWD
SOLENOID VALVE CIRCUIT MALFUNCTION,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>

P1710

Torque Converter Tur-
bine 2 Speed Signal Cir-
cuit 2 Malfunction

Torque converter sensor 2 mal-
function, input circuit, ground,
power open, short circuit

<Ref. to 5AT(diag)-93, DTC P1710 TORQUE
CONVERTER TURBINE 2 SPEED SIGNAL
CIRCUIT 2 MALFUNCTION, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

P1718

AT CAN Communication
Circuit

CAN communication line bus-off
open circuit, ECM short circuit,
ABS/VDCCM or integrated CM
malfunction

<Ref. to 5AT(diag)-95, DTC P1718 AT CAN
COMMUNICATION CIRCUIT, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

P1760

Lateral Acceleration
Sensor Performance
Problem

Faulty lateral G sensor

<Ref. to 5AT(diag)-96, DTC P1760 LATERAL
ACCELERATION SENSOR PERFORMANCE
PROBLEM, Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>

P1761

Lateral Acceleration
Sensor Circuit Low

Lateral G sensor is faulty, input
signal circuit is open, or CAN
communication failure occurs

<Ref. to 5AT(diag)-98, DTC P1761 LATERAL
ACCELERATION SENSOR CIRCUIT LOW,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>

P1762

Lateral Acceleration
Sensor Circuit High

Lateral G sensor is faulty or input
signal circuit is shorted.

<Ref. to 5AT(diag)-100, DTC P1762 LATERAL
ACCELERATION SENSOR CIRCUIT HIGH,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>

P1817

SPORT Mode Switch
Circuit (Manual Switch)

Manual mode switch is open,
shorted, or switch malfunction

<Ref. to 5AT(diag)-103, DTC P1817 SPORT
MODE SWITCH CIRCUIT (MANUAL
SWITCH), Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>

P1840

Transmission Fluid Pres-
sure Sensor/Switch A
Circuit

Fr/B oil pressure switch is open or
shorted, or switch malfunction

<Ref. to 5AT(diag)-105, DTC P1840 TRANS-
MISSION FLUID PRESSURE SENSOR/
SWITCH A CIRCUIT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P1841

Transmission Fluid Pres-
sure Sensor/Switch B
Circuit

Fwd/B oil pressure switch is open
or shorted, or switch malfunction

<Ref. to 5AT(diag)-105, DTC P1841 TRANS-
MISSION FLUID PRESSURE SENSOR/
SWITCH B CIRCUIT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P1842

Transmission Fluid Pres-
sure Sensor/Switch C
Circuit

I/C oil pressure switch is open or
shorted, or switch malfunction.

<Ref. to 5AT(diag)-105, DTC P1842 TRANS-
MISSION FLUID PRESSURE SENSOR/
SWITCH C CIRCUIT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P1843

Transmission Fluid Pres-
sure Sensor/Switch D
Circuit

D/C oil pressure switch is open or
shorted, or switch malfunction.

<Ref. to 5AT(diag)-105, DTC P1843 TRANS-
MISSION FLUID PRESSURE SENSOR/
SWITCH D CIRCUIT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

P1844

Transmission Fluid Pres-
sure Sensor/Switch E
Circuit

H&LR/C oil pressure switch is
open or shorted, or switch mal-
function.

<Ref. to 5AT(diag)-105, DTC P1844 TRANS-
MISSION FLUID PRESSURE SENSOR/
SWITCH E CIRCUIT, Diagnostic Procedure
with Diagnostic Trouble Code (DTC).>

DTC

Item

Contents of diagnosis

Reference