P1505

DTC P1505 - IDLE CONTROL SYSTEM CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Immediately at fault recognition

TROUBLE SYMPTOM:
- Erroneous idling
- Engine stalls.
- Engine breathing

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.

Wiring Diagram:

WIRING DIAGRAM

10CL1: CHECK THROTTLE CABLE.

CHECK: Does throttle cable have play for adjustment?

YES: Go to step 10CL2.

NO: Adjust throttle cable.

10CL2: CHECK OUTPUT SIGNAL FROM ECM.

1. Turn ignition switch to ON.

Connector & Terminal - [(B134) No.5 (+) - Chassis Ground (-)]:

2. Measure voltage between ECM and chassis ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 10CL3.

NO: Go to step 10CL4.

10CL3: CHECK OUTPUT SIGNAL FROM ECM.

1. Turn ignition switch to OFF.
2. Disconnect connector from idle air control solenoid valve.
3. Turn ignition switch to ON.

Connector & Terminal - [(B134) No.5 (+) - Chassis Ground (-)]:

4. Measure voltage between ECM and chassis ground.

CHECK: Is the voltage more than 10 V?

YES: Repair battery short circuit in harness between ECM and idle air control solenoid valve connector. After repair, replace ECM.
NO: Replace idle air control solenoid valve and ECM .

10CL4: CHECK OUTPUT SIGNAL FROM ECM.

Connector & Terminal - [(B134) No.5 (+) - Chassis Ground (-)]:

Measure voltage between ECM and chassis ground.

CHECK: Does the voltage change more than 10 V by shaking harness and connector of ECM while monitoring the value with voltage meter?

YES: Repair battery short circuit in harness between ECM and idle air control solenoid valve connector. After repair, replace ECM.
NO: Contact with Subaru of America (SOA) service.

NOTE: Inspection by Subaru of America's DTM is required, because probable cause is deterioration of multiple parts.