AUTOMATIC TRANSMISSION (DIAGNOSTICS)(4AT) > Diagnostic Procedure for Subaru Select Monitor Communication

COMMUNICATION FOR INITIALIZING IMPOSSIBLE

DIAGNOSIS:

Defective harness connector

TROUBLE SYMPTOM:

Subaru Select Monitor communication failure

WIRING DIAGRAM:

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1.CHECK INSTALLATION OF TCM CONNECTOR.

Turn the ignition switch to OFF.

Is TCM connector connected to TCM?

Connect the TCM connector to TCM.

2.CHECK SUBARU SELECT MONITOR POWER SUPPLY CIRCUIT.

Measure the voltage between data link connector and chassis ground.

Connector & terminal

(B40) No. 16 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair harness connector between the battery and data link connector, and poor contact of the connector.

3.CHECK SUBARU SELECT MONITOR GROUND CIRCUIT.

Measure the resistance of the harness between data link connector and engine ground.

Connector & terminal

(B40) No. 4 — Engine ground:

(B40) No. 5 — Engine ground:

Is the resistance less than 1 Ω?

Repair the open circuit between data link connector and engine ground.

4.CHECK COMMUNICATION OF SUBARU SELECT MONITOR.

1) Turn the ignition switch to ON.

2) Check communication with the transmission.

Is the name of system displayed on Subaru Select Monitor?

5.CHECK COMMUNICATION OF SUBARU SELECT MONITOR.

1) Turn the ignition switch to OFF.

2) Disconnect the TCM connector.

3) Turn the ignition switch to ON.

4) Check communication with the engine system.

Is the name of system displayed on Subaru Select Monitor?

6.CHECK OUTPUT SIGNAL OF TCM.

1) Turn the ignition switch to OFF.

2) Connect the connector to TCM.

3) Disconnect the connectors from control modules connected to the data link connector (B40) No. 7, excluding TCM and ECM.

CAUTION:

When disconnecting the connector from airbag control module, always follow the precautions on AB section.

4) Turn the ignition switch to ON.

5) Check communication with the transmission system.

Is the name of system displayed on Subaru Select Monitor?

Check each control module.

7.CHECK HARNESS CONNECTOR BETWEEN EACH CONTROL MODULE AND DATA LINK CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors of all control modules connected to the data link connector (B40) No. 7.

3) Measure the resistance between TCM connector and chassis ground.

Connector & terminal

(B40) No. 7 — Chassis ground:

Is the resistance 1 MΩ or more?

Check harness and connector between each control module and data link connector.

8.CHECK OUTPUT SIGNAL OF TCM.

1) Turn the ignition switch to ON.

2) Measure the voltage between TCM and chassis ground.

Connector & terminal

(B40) No. 7 (+) — Chassis ground (−):

Is the voltage 1 V or more?

Check harness and connector between each control module and data link connector.

9.CHECK HARNESS CONNECTOR BETWEEN TCM AND DATA LINK CONNECTOR.

Measure the resistance between TCM connector and data link connector.

Connector & terminal

(B40) No. 7 — (B54) No. 8:

Is the resistance less than 1 Ω?

Check the harness and connector between TCM and data link connector.

10.CHECK INSTALLATION OF TRANSMISSION HARNESS CONNECTOR.

Is the transmission harness connector connected to bulkhead harness connector?

Connect the bulkhead harness connector to transmission harness connector.

11.CHECK POOR CONTACT OF CONNECTORS.

Is there poor contact of control module power supply and data link connector?

Repair the poor contact.

12.CHECK TCM POWER SUPPLY.

1) Disconnect the connector from TCM.

2) Turn the ignition switch to ON.

3) Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(B54) No. 25 (+) — Chassis ground (−):
(B54) No. 26 (+) — Chassis ground (−):
(B54) No. 27 (+) — Chassis ground (−):

Is the voltage 10 — 13 V?

13.CHECK M/B 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. If the replaced fuse has blown out easily, repair short circuit of harness between fuse and TCM.

Repair the open circuit of harness between fuse and TCM, or fuse and battery, and poor contact of the connector.

14.CHECK IGNITION POWER SUPPLY CIRCUIT.

1) Turn the ignition switch to ON.

2) Measure the ignition power supply voltage between TCM connector and chassis ground.

Connector & terminal

(B54) No. 1 (+) — Chassis ground (−):
(B54) No. 2 (+) — Chassis ground (−):

Is the voltage 10 — 13 V?

15.CHECK F/B FUSE (NO. 12).

Remove the fuse (No. 12).

Is the fuse (No. 12) blown out?

Replace the fuse. If the replaced fuse has blown out easily, repair short circuit of harness between fuse and TCM.

Repair the open circuit of harness between fuse and TCM, or fuse and battery, and poor contact of the connector.

16.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 connector and transmission connector.

Connector & terminal

(B54) No. 20 — (B11) No. 20:
(B54) No. 21 — (B11) No. 20:
(B54) No. 22 — (B11) No. 19:
(B54) No. 23 — (B11) No. 19:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between TCM and transmission harness connector, and poor contact of connector.

17.CHECK HARNESS CONNECTOR BETWEEN TRANSMISSION AND TRANSMISSION GROUND.

Measure the resistance of harness between transmission connector and transmission ground.

Connector & terminal

(T4) No. 19 — Transmission ground:

(T4) No. 20 — Transmission ground:

Is the resistance less than 1 Ω?

Repair the open circuit of the harness between transmission and transmission ground.

18.CHECK POOR CONTACT OF CONNECTORS.

Is there poor contact of TCM power supply, ground and data link connector?

Repair the connector.

Replace the TCM.