I tested the idle valve: under 12V it open fully and its resistance is about 8 ohms.
Now I'd like to check if the ECU is sending correct information to it: what kind of voltage should I expect on it, when:

- ignition is On, engine is Off?

- engine running, engine temperature cold (just started 70 F), on average (I know it must be fluctuating)?

- engine running, engine temperature reached operating temperature, on average again?

Thanks.

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From 300CE to SLK230K

Not really a voltage signal but a duty cycle reading.

That uses a 30% duty cycle. Only when running.

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