Subaru Legacy IV (2008 year). Service manual - part 771

5AT(diag)-99

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

CHECK OPEN CIRCUIT IN LATERAL G SEN-
SOR OUTPUT HARNESS AND GROUND
HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM.
3) Measure the resistance between TCM con-
nector terminals.

Connector & terminal

(B54) No. 18 — (B55) No. 7:

Is the resistance 5.0 — 6.0 k

:? Go to step 9.

Repair the harness
between lateral G
sensor and TCM.

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

Connector & terminal

(B54) No. 18 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 10.

Repair the harness
between lateral G
sensor and TCM.
Replace the TCM.
<Ref. to 5AT-60,
Transmission Con-
trol Module
(TCM).>

CHECK LATERAL G SENSOR.
1) Remove the console box.
2) Remove the lateral G sensor from vehicle.
3) Connect the connector to lateral G sensor.
4) Connect the TCM connector.
5) Turn the ignition switch to ON.
6) Measure the voltage between lateral G sen-
sor connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 2.3 — 2.7 V when
lateral G sensor is in horizontal
position?

Go to step 11.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 3.3 — 4.3 V when
lateral G sensor is inclined 90°
to right?

Go to step 12.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 0.7 — 1.7 V when
lateral G sensor is inclined 90°
to left?

Go to step 13.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK TCM.
1) Turn the ignition switch to OFF.
2) Connect all connectors.
3) Perform the Clear Memory Mode.
4) Perform the Inspection Mode.
5) Read the DTC.

Is the same DTC displayed?

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

Go to step 14.

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC.

Temporary poor
contact occurs.

Step

Check

Yes

5AT(diag)-100

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

AK:DTC P1762 LATERAL ACCELERATION SENSOR CIRCUIT HIGH

DTC DETECTING CONDITION:
Lateral G sensor output voltage fault
WIRING DIAGRAM:

AT-04479

B359

B55

TCM

B359

1 2 3

B55

10 11 12 13 14 15

17 18 19

20
28

21 22 23

26 27

34 35

B54

10 11 12 13 14 15

17 18 19 20
28

21 22 23

33 34 35

LATERAL G SENSOR

B54

A18

5AT(diag)-101

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Step

Check

Yes

CHECK VEHICLE CONDITION.

Is the vehicle a model with
VDC, which has the VDC OFF
switch on the instrument panel?

Go to step 2.

Go to step 4.

CHECK DTC OF TCM.

Is DTC of AT CAN communica-
tion detected?

Perform the diag-
nosis according to
DTC.

Go to step 3.

CHECK DTC OF ABS.

Is DTC of ABS detected?

Perform the diag-
nosis according to
DTC of ABS.

Temporary poor
contact occurs.
Recheck for defec-
tive parts in har-
ness and
connectors.

CHECK OUTPUT OF LATERAL G SENSOR
USING SUBARU SELECT MONITOR.
Read the value of “Lateral G Sensor” using
Subaru Select Monitor.

Is the reading indicated on
monitor display 2.3 to 2.7 V
when lateral G sensor is level?

Go to step 5.

Go to step 8.

CHECK POOR CONTACT IN CONNECTOR.

Is there poor contact in connec-
tor between TCM and lateral G
sensor?

Repair the connec-
tor.

Go to step 6.

CHECK ABSCM&H/U.
1) Connect all connectors.
2) Perform the Clear Memory Mode.
3) Perform the Inspection Mode.
4) Read the DTC.

Is the same DTC displayed?

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

Go to step 7.

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC.

Temporary poor
contact occurs.

CHECK INFORMATION STORED IN FREEZE
FRAME DATA.
Read the value of “Lateral G Sensor” using
Subaru Select Monitor.

Is the reading on monitor 4.65 V
or more?

Go to step 9.

Go to step 15.

Connector & terminal

(B55) No. 9 — (B54) No. 18:

Is the resistance 4.3 — 4.9 k

:? Go to step 10.

Repair the harness
connector between
the lateral G sen-
sor and
ABSCM&H/U.

CHECK BATTERY SHORT OF HARNESS.
1) Turn the ignition switch to OFF.
2) Remove the console box.
3) Disconnect the connector from the lateral G
sensor.
4) Disconnect the connector from TCM.
5) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 7 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step 11.

Repair the harness
between lateral G
sensor and TCM.

CHECK BATTERY SHORT OF HARNESS.
1) Turn the ignition switch to ON.
2) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 7 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step 12.

Repair the harness
between lateral G
sensor and TCM.

CHECK POOR CONTACT IN CONNECTOR.

Is there poor contact in connec-
tor between TCM and lateral G
sensor?

Repair the connec-
tor.

Go to step 13.

5AT(diag)-102

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

CHECK TCM.
1) Connect all connectors.
2) Perform the Clear Memory Mode.
3) Perform the Inspection Mode.
4) Read the DTC.

Is the same DTC displayed?

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

Go to step 14.

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC.

Temporary poor
contact occurs.

CHECK LATERAL G SENSOR INPUT VOLT-
AGE.
1) Turn the ignition switch to OFF.
2) Remove the console box.
3) Remove the lateral G sensor from vehicle.
(Do not disconnect the connector.))
4) Turn the ignition switch to ON.
5) Measure the voltage between lateral G sen-
sor connector terminals.

Connector & terminal

(B359) No. 1 (+) — No. 2 (–):

Is the voltage 4.75 — 5.25 V?

Go to step 16.

Repair the harness
between lateral G
sensor and TCM.

Connector & terminal

(B55) No. 9 — No. 7:

Is the resistance 5.0 — 5.6 k

:? Go to step 17.

Repair the harness
between lateral G
sensor and TCM.

CHECK LATERAL G SENSOR.
1) Connect the connector to lateral G sensor.
2) Connect the TCM connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between lateral G sen-
sor connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 2.3 — 2.7 V when
lateral G sensor is in horizontal
position?

Go to step 18.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 3.3 — 4.3 V when
lateral G sensor is inclined 90°
to right?

Go to step 19.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (–):

Is the voltage 0.7 — 1.7 V when
lateral G sensor is inclined 90°
to left?

Go to step 20.

Replace the lateral
G sensor. <Ref. to
5AT-61, Lateral G
Sensor.>

CHECK POOR CONTACT IN CONNECTOR.
Turn the ignition switch to OFF.

Is there poor contact in connec-
tor between TCM and lateral G
sensor?

Repair the connec-
tor.

Go to step 21.

CHECK ABSCM&H/U.
1) Connect all connectors.
2) Perform the Clear Memory Mode.
3) Perform the Inspection Mode.
4) Read the DTC.

Is the same DTC displayed?

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

Go to step 22.

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC.

Temporary poor
contact occurs.

Step

Check

Yes

Content .. 769 770 771 772 ..