Zazz just to be clear, Wal's in general are all active. Bass with preamp = active bass.
what you speak of are settings to "sound like a passive bass".

which you can probably do with any active bass, but by definition, passive basses do not require a battery since the circuitry only deals with in most cases a single capacitor and pots to vary impedance to cut/adjust tone/volume.
active basses are more robust and hotter (as far as signals go) since they have a preamp. A preamp also allows the feature of cutting or boosting frequencies and typically more tone adjustments; bass, treble, mids, etc. So just like an outboard preamp, if you lose electricity in your house you get no sound. so if you got a dead battery you get no sound as well. basses with the option of going passive/active, they typically have a switch that bypasses the preamp and uses a "basic" circuity for tone/volume. Wal basses do not utilize this and so don't confuse the push/pull knobs as a passive/active switch

Quoting Wal's site:
Pulling-up the knob produces a quasi-parametric boost of about 10dB to the harmonics which lie at or near the roll-off frequency set by the rotary position.
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with all this being said, yes in general
Wal's are all active unless you have a Pro I, Pro II or if you have one of the few passive Mark custom series passive
Hope this clears all future confusion