Contents Wiring diagrams Section: Testing & Diagnostics All sections

Engine Controls - Tests W/codes: Diagnosis Subaru Legacy BD/BG/BK

Testing & Diagnostics 2 illustrations ~284 words

RETRIEVING DTC(S)

Note. Subaru Select Monitor (SSM) or an OBD-II scan tool must be used to perform self-diagnostic tests. Follow scan tool manufacturer's instructions for proper operation. SSM can be plugged into either the OBD-II DLC or the dedicated SSM test connectors behind the dash.

Connect scan tool to DLC located on lower left side of dash. (Scheme 1)or (Scheme 2). Retrieve Diagnostic Trouble Codes (DTCs) and freeze frame data, following scan tool manufacturer's instructions. Scan tool functions consist of

  1. MODE 01 - Current powertrain diagnostic data
  2. MODE 02 - Powertrain freeze frame data
  3. MODE 03 - Emission-related powertrain DTCs
  4. MODE 04 - Clear/reset emission-related diagnostic information
  5. MODE 05 - Oxygen sensor monitoring test results

Scheme 1

Scheme 1

Scheme 2

Scheme 2

CLEARING DTC(S)

Clear DTC(s) using scan tool (MODE 04). Refer to scan tool manufacturer's instruction. Disconnecting battery negative battery terminal will also clear DTC(s), but radio presets will be erased.

TROUBLE CODE DEFINITION

DTCSSM Title (1)Circuit AffectedProbable Cause
P0100QAAirflow Sensor CircuitOpen/Short Circuit
P0101QA-RAirflow Sensor Circuit Range/Performance ProblemBad Sensor
P0105P-SPressure Sensor Circuit MalfunctionOpen/Short Circuit
P0106P-RPressure Sensor Range/ PerformanceBad Sensor
P0115TWCoolant Temperature Sensor Circuit MalfunctionOpen/Short Circuit
P0120THVThrottle Position Sensor Circuit MalfunctionOpen/Short Circuit
P0121TH-RThrottle Position Sensor Range/PerformanceBad Sensor
P0125TW-CLCoolant Temp Too Low For Closed Loop ControlBad Sensor
P0130FO2-VFront O2 Sensor Circuit MalfunctionBad Sensor, Bad Fuel
P0133FO2-RFront O2 Sensor Circuit Slow ResponseBad Sensor, Bad Fuel
P0135FO2HFront O2 Sensor Heater Circuit MalfunctionOpen/Short Circuit
P0136RO2-VRear O2 Sensor Circuit MalfunctionBad Sensor, Bad Fuel
P0139RO2-RRear O2 Sensor Circuit Slow ResponseBad Sensor, Bad Fuel
P0141RO2HRear O2 Sensor Heater Circuit MalfunctionOpen/Short Circuit
P0170FUELFuel Trim MalfunctionAny Part Of Fuel System
P0201INJ1Fuel Injector No 1Inoperative Fuel Injector
P0202INJ2Fuel Injector No 2Inoperative Fuel Injector
P0203INJ3Fuel Injector No 3Inoperative Fuel Injector
P0204INJ4Fuel Injector No 4Inoperative Fuel Injector
P0301MIS-1Cylinder 1 Misfire DetectedBad Igniter
P0302MIS-2Cylinder 2 Misfire DetectedBad Igniter
P0303MIS-3Cylinder 3 Misfire DetectedBad Igniter
P0304MIS-4Cylinder 4 Misfire DetectedBad Igniter
P0325KNOCKKnock Sensor Circuit MalfunctionOpen/Short Circuit
P0335CRANKCrankshaft Position SensorOpen/Short Circuit, Bad Sensor
P0340CAMCamshaft Position SensorOpen/Short Circuit, Bad Sensor
P0400EGREGR FlowFaulty EGR Sys. Function
P0403EGRSOLEGR CircuitEGR System Malfunction
P0420CATCAT Efficiency Below ThresholdBad CAT, Bad Fuel Control
P0441CPC-FIncorrect EVAP Purge FlowBad Purge Control Solenoid Valve
P0443CPCEVAP Circuit MalfunctionOpen/Short Circuit
P0500VSPVehicle Speed SensorBad Sensor
P0505ISCIdle Control SystemOpen/Short Circuit, Bad Idle Solenoid
P0506ISC-LIdle RPM Too LowBad Idle Solenoid, Air By-Pass
P0507ISC-HIdle Too HighIdle Solenoid, Air Leaks
P0600Serial Communication Link MalfunctionOpen/Short Circuit
P0601RAMMemory Check ErrorECM
(1) SSM: Subaru select monitor.
(1)SSM: Subaru select monitor.

OBD II DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION CHART

Diagnosis & Repair Procedure

If only code P0101 is displayed, replace MAF sensor and retest. If other codes are displayed, diagnose and repair those codes first and retest.

DTC 507 (ISC_H) - IDLE CONTROL SYSTEM RPM HIGHER THAN EXPECTED

Note. Refer to illustration for connector and terminal identification. see scheme 3- see scheme 28.

  1. Perform tests and repairs for «DTC P0505»(ref-26154-S05622943112001010500000) .
  2. Turn ignition to ON. Start engine and allow to idle. Check intake manifold, idle air control solenoid valve and throttle body for loose installation and gasket for cracks, by-pass hose for loose connection or cracking and vacuum hoses for disconnection or cracking. Repair as necessary. If no damage is noted, replace idle air control solenoid valve.