Possible causes

– Faulty Secondary Shutter Valve (SSV) Solenoid Valve
– Secondary Shutter Valve Solenoid Valve harness is open or shorted
– Secondary Shutter Valve (SSV) solenoid valve circuit poor electrical connection

When is the code detected?

The Engine Control Module (ECM) has detected an improper signal from the Secondary Shutter Valve (SSV)

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0660 MAZDA Description

The Powertrain Control Module (PCM) monitors the Secondary Shutter Valve (SSV) solenoid valve control voltage when the PCM turns the SSV solenoid valve off. If the control voltage is less than 5.8 V, the PCM determines that the SSV solenoid valve control circuit voltage is low.

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MAZDA Technical Service Bulletins for P0660 code