ENGINE (DIAGNOSTICS)(H4DO) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC P2101 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:

Immediately at fault recognition

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After repairing or replacing the defective part, perform the Clear Memory Mode and Inspection Mode .

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK ELECTRONIC THROTTLE CONTROL RELAY.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control relay.

3) Connect the battery to terminals No. 1 and No. 3 of electronic throttle control relay.

4) Measure the resistance between electronic throttle control relay terminals.

Terminals

No. 2 — No. 4:

Is the resistance less than 1 Ω?

Replace the electronic throttle control relay.

2.CHECK POWER SUPPLY OF ELECTRONIC THROTTLE CONTROL RELAY.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic throttle control relay connector and chassis ground.

Connector & terminal

(B309) No. 1 (+) — Chassis ground (−):

(B309) No. 2 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair the open or ground short circuit of power supply circuit.

3.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM.

3) Turn the ignition switch to ON.

4) Measure the voltage between electronic throttle control relay connector and chassis ground.

Connector & terminal

(B309) No. 3 (+) — Chassis ground (−):

Is the voltage 10 V or more?

Repair the short to power supply in harness between ECM and electronic throttle control relay.

4.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY.

1) Turn the ignition switch to OFF.

2) Measure the resistance between electronic throttle control relay connector and chassis ground.

Connector & terminal

(B309) No. 3 — Chassis ground:

(B309) No. 4 — Chassis ground:

Is the resistance 1 MΩ or more?

Repair the ground short circuit of harness between ECM and electronic throttle control relay.

5.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY.

Measure the resistance between ECM connector and electronic throttle control relay connector.

Connector & terminal

(B135) No. 6 — (B309) No. 3:

(B136) No. 1 — (B309) No. 4:

(B136) No. 2 — (B309) No. 4:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between ECM and electronic throttle control relay.

6.CHECK SENSOR OUTPUT.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connector terminals.

Connector & terminal

(B137) No. 24 (+) — (B137) No. 31 (−):

Is the voltage 0.3 V or more?

7.CHECK SENSOR OUTPUT.

Measure the voltage between ECM connector terminals.

Connector & terminal

(B137) No. 23 (+) — (B137) No. 31 (−):

Is the voltage less than 4.8 V?

8.CHECK POOR CONTACT.

Check poor contact in connector between ECM and electronic throttle.

Is there poor contact?

Repair the poor contact.

9.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM and electronic throttle.

3) Measure the resistance between ECM connector and electronic throttle connector.

Connector & terminal

(B137) No. 23 — (E57) No. 5:

(B137) No. 24 — (E57) No. 2:

(B137) No. 25 — (E57) No. 4:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between ECM and electronic throttle connector.

10.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B137) No. 25 — Chassis ground:

(B137) No. 23 — Chassis ground:

(B137) No. 24 — Chassis ground:

Is the resistance 1 MΩ or more?

Repair the ground short circuit of harness between ECM and electronic throttle connector.

11.CHECK SENSOR POWER SUPPLY.

1) Connect the ECM connector.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 4 (+) — Engine ground (−):

Is the voltage 4.5 — 5.5 V?

Repair the poor contact of ECM connector. Replace the ECM if defective.

12.CHECK SHORT CIRCUIT IN ECM.

1) Turn the ignition switch to OFF.

2) Measure the resistance between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 2 — Engine ground:

(E57) No. 5 — Engine ground:

Is the resistance 10 Ω or more?

Repair the poor contact of ECM connector. Replace the ECM if defective.

13.CHECK SENSOR OUTPUT.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Read the data of main throttle sensor signal using Subaru Select Monitor.

NOTE:

For detailed operation procedure, refer to “READ CURRENT DATA FOR ENGINE”.

Is the voltage 0.5 — 1.0 V?

14.CHECK SENSOR OUTPUT.

Read the data of sub throttle sensor signal using Subaru Select Monitor.

NOTE:

For detailed operation procedure, refer to “READ CURRENT DATA FOR ENGINE”.

Is the voltage 0.5 — 1.0 V?

15.CHECK POOR CONTACT.

Check poor contact in connector between ECM and electronic throttle.

Is there poor contact?

Repair the poor contact.

16.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM and electronic throttle.

3) Measure the resistance between ECM connector and electronic throttle connector.

Connector & terminal

(B137) No. 23 — (E57) No. 5:

(B137) No. 24 — (E57) No. 2:

(B137) No. 31 — (E57) No. 1:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between ECM and electronic throttle.

17.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

1) Connect the ECM connector.

2) Measure the resistance between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 1 — Engine ground:

Is the resistance less than 5 Ω?

Repair the poor contact of ECM connector. Replace the ECM if defective.

18.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 4 (+) — Engine ground (−):

Is the voltage less than 10 V?

Repair the short to power supply in harness between ECM connector and electronic throttle connector.

19.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

Measure the voltage between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 5 (+) — Engine ground (−):

(E57) No. 2 (+) — Engine ground (−):

Is the voltage less than 10 V?

Repair the ground short circuit of harness between ECM connector and electronic throttle connector.

20.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE.

1) Turn the ignition switch to OFF.

2) Remove the ECM.

3) Measure the resistance between ECM connectors.

Connector & terminal

(B137) No. 23 — (B137) No. 25:

(B137) No. 24 — (B137) No. 25:

Is the resistance 1 MΩ or more?

Repair the battery short circuit of harness.

21.CHECK SENSOR OUTPUT.

1) Turn the ignition switch to OFF.

2) Connect the connectors except for electric throttle control relay.

3) Turn the ignition switch to ON.

4) Read the data of main throttle sensor signal using Subaru Select Monitor.

NOTE:

For detailed operation procedure, refer to “READ CURRENT DATA FOR ENGINE”.

Is the voltage 0.5 — 1.0 V?

Repair the poor contact of electronic throttle connector. Replace the electronic throttle if defective.

22.CHECK SENSOR OUTPUT.

Read the data of sub throttle sensor signal using Subaru Select Monitor.

NOTE:

For detailed operation procedure, refer to “READ CURRENT DATA FOR ENGINE”.

Is the voltage 0.5 — 1.0 V?

Repair the poor contact of ECM connector. Replace the electronic throttle if defective.

23.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE MOTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM and electronic throttle.

3) Measure the resistance between ECM connector and electronic throttle connector.

Connector & terminal

(B137) No. 2 — (E57) No. 3:

(B137) No. 3 — (E57) No. 3:

(B137) No. 4 — (E57) No. 6:

(B137) No. 5 — (E57) No. 6:

Is the resistance less than 1 Ω?

Repair the open circuit of harness between ECM and electronic throttle.

24.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE MOTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 3 (+) — Engine ground (−):

(E57) No. 6 (+) — Engine ground (−):

Is the voltage less than 10 V?

Repair the short circuit of harness between the ECM and electronic throttle.

25.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE MOTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM.

3) Measure the resistance between electronic throttle connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

(E57) No. 6 — Engine ground:

Is the resistance 1 MΩ or more?

Repair the ground short circuit of harness between ECM and electronic throttle control relay.

26.CHECK ELECTRONIC THROTTLE MOTOR HARNESS.

Measure the resistance between electronic throttle connector terminals.

Connector & terminal

(E57) No. 3 — (E57) No. 6:

Is the resistance 1 MΩ or more?

Repair the short circuit of harness between ECM and electronic throttle.

27.CHECK ELECTRONIC THROTTLE GROUND CIRCUIT.

Measure the resistance between ECM connector and chassis ground.

Connector & terminal

(B137) No. 1 — Chassis ground:

(B134) No. 6 — Chassis ground:

Is the resistance less than 10 Ω?

Repair the open circuit of harness between ECM and chassis ground.

28.CHECK ELECTRONIC THROTTLE.

Measure the resistance between electronic throttle terminals.

Terminals

No. 3 — No. 6:

Is the resistance less than 50 Ω?

Replace the electronic throttle.

29.CHECK ELECTRONIC THROTTLE.

Move the throttle valve to the fully open and fully closed positions with fingers.

Check that the valve returns to the specified position when releasing fingers.

Does the valve return to the specified position? Standard value: 3 mm (0.12 in) from fully closed position

Repair the poor contact of ECM connector. Replace the ECM if defective.

Replace the electronic throttle.