Possible causes

– Engine Control Module (ECM) may be faulty
– ECM harness power supply circuit is open or shorted
– ECM harness ground circuit is open or shorted

Tech notes

Check the PCM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the PCM.

When is the code detected?

Indicates the PCM has experienced an internal memory fault.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Engine may not start

P0605 SUBARU Description

The Engine Control Module (ECM) continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check insures that the ECM is functioning properly. If any malfunction is detected, the ECM sets the P0605 code and illuminates the MIL.

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