Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc p2102 throttle actuator "a" control motor circuit low

Subaru Legacy BN/BS (2015-2019) Service Manual / Engine (diagnostics)(h4do) / Diagnostic procedure with diagnostic trouble code (dtc) / Dtc p2102 throttle actuator "a" control motor circuit low

DTC DETECTING CONDITION:

Immediately at fault recognition

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode Clear Memory Mode > OPERATION, and Inspection Mode Inspection Mode > PROCEDURE.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FB (WITHOUT PUSH BUTTON START) Engine Electrical System > WIRING DIAGRAM

• Engine Electrical System ENGINE TYPE FB (WITH PUSH BUTTON START) Engine Electrical System > WIRING DIAGRAM

STEP	CHECK	YES	NO
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. 13 and No. 14 of electronic throttle control relay. 4) Measure the resistance between electronic throttle control relay terminals. Terminals No. 22 — No. 23:	Is the resistance less than 1 --	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P2102 THROTTLE ACTUATOR "A" CONTROL MOTOR CIRCUIT LOW	Replace the electronic throttle control relay. Electronic Throttle Control Relay
2.CHECK POWER SUPPLY OF ELECTRONIC THROTTLE CONTROL RELAY. Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B48) No. 22 (+) — Chassis ground (−):	Is the voltage 10 V or more-	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P2102 THROTTLE ACTUATOR "A" CONTROL MOTOR CIRCUIT LOW	Repair the open or short to ground in the power supply circuit.
3.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. 1) Disconnect the connector from ECM. 2) Turn the ignition switch to ON. 3) Measure the voltage between electronic throttle control relay connector and chassis ground. Connector & terminal (B48) No. 20 (+) — Chassis ground (−):	Is the voltage 10 V or more-	Repair the short circuit to power in the harness between ECM connector and electronic throttle control relay connector.	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P2102 THROTTLE ACTUATOR "A" CONTROL MOTOR CIRCUIT LOW
4.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. 1) Turn the ignition switch to OFF. 2) Measure the resistance between electronic throttle control relay connector and chassis ground. Connector & terminal (B48) No. 20 — Chassis ground: (B48) No. 23 — Chassis ground:	Is the resistance 1 M- or more-	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P2102 THROTTLE ACTUATOR "A" CONTROL MOTOR CIRCUIT LOW	Repair the short circuit to ground in harness between ECM connector and electronic throttle control relay connector.
5.CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL RELAY CONNECTOR. Measure the resistance between ECM connector and electronic throttle control relay connector. Connector & terminal (B134) No. 65 — (B48) No. 20: (B134) No. 13 — (B48) No. 23:	Is the resistance less than 1 --	Repair the poor contact of ECM connector.	Repair the open circuit in harness between ECM connector and electronic throttle control relay connector.

1. OUTLINE OF DIAGNOSIS

Judge as NG when the electronic throttle control power is not supplied even when ECM sets the electric control throttle relay to ON.

2. COMPONENT DESCRIPTION

(1)	Engine control module (ECM)	(3)	Drive circuit	(5)	Motor
(2)	Voltage detection circuit	(4)	Electronic throttle control relay

3. EXECUTION CONDITION

Secondary Parameters	Execution condition
Battery voltage	≥ 11 V
Electronic throttle control relay output	ON

4. GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

5. DIAGNOSTIC METHOD

If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.

Judgment Value

Malfunction Criteria	Threshold Value
Motor power voltage	≤ 5 V

Time Needed for Diagnosis: 352 ms

Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.

Dtc p2103 throttle actuator "a" control motor circuit high

DTC DETECTING CONDITION:Immediately at fault recognitionCAUTION:After servicing or replacing faulty parts, perform Clear Memory Mode Clear Memory Mode > OPERATION, and Inspection Mode Inspection Mod ...

Dtc p2101 throttle actuator "a" control motor circuit range/performance

DTC DETECTING CONDITION:Immediately at fault recognitionTROUBLE SYMPTOM:• Improper idling• Poor driving performance• Engine stalls.CAUTION:After servicing or replacing faulty parts, ...

Other materials:

Procedure
1. CHECK REFRIGERANT GAS PRESSURE1. Prepare the vehicle.NOTE:Check that the ambient temperature is 25 — 40°C (77 — 104°F) and that the humidity is 30% — 80%.• Place the vehicle in the shade and windless condition, and open the front hood.• Open the front windows and c ...