Parts for your 2004 Toyota Bb-Cabin filter

2004 Toyota bB cabin filter — what it does and how to look after it

The 2004 Toyota bB (model codes NCP30/NCP31/NCP35, same platform as the first‑gen Scion xB) is designed to use a serviceable cabin air filter located behind the glovebox. Technical references: Toyota Electronic Parts Catalogue (EPC) for NCP30/31/35 lists a cabin “Air Filter (Air Refiner)” with part number 87139‑52020 for the heater/aircon unit, and the Toyota Repair Manual for bB/ist (Air Conditioning section: Air Filter Removal/Installation) details glovebox access to the filter slot. Many export cars left the factory without the element fitted, but the housing and filter door are present, so installing a filter is straightforward and fully supported by Toyota’s documentation.

For anyone dailying a 2004 bB, the cabin filter quietly does the hard yards. It traps dust, pollen, road grime and soot before they hit the evaporator core and before they end up in the cabin air you’re breathing. That means clearer screens, cleaner vents, less musty odour after rain, and better protection for the HVAC hardware. In Aussie and Kiwi conditions—bushfire smoke, coastal salt, unsealed roads—a good filter makes a noticeable difference.

Replacement is quick. Drop the glovebox by unhooking the damper and squeezing the sides, pop off the small rectangular filter door, slide the old element out, and insert the new one with the airflow arrow pointing the right way (usually down). Refit the door and glovebox and you’re done. If the car never had an element installed, you’ll still find the slot and door there, just slide a new filter in.

How often? Plan on every 12 months or 15,000 km—whichever comes first. If you’re often on dusty gravel, park under trees, or deal with seasonal smoke and pollen, shorten that interval. Signs it’s due include weak airflow even on high fan speed, a whistling fan, foggy windows that take ages to clear, or a stale smell when you first switch the air‑con on. During servicing, it’s smart to vacuum out leaves from the intake plenum and check the filter door seal. Charcoal/activated‑carbon elements are worth a look if you want extra odour control, especially for city traffic.

Stick with a genuine Toyota element or a quality aftermarket equivalent sized for the bB’s HVAC box (the EPC lists 87139‑52020 for these models). If in doubt, match by VIN or measure the old filter. It’s a small job that keeps the bB feeling fresh and the air‑con breathing freely.

Where is the cabin filter on a 2004 Toyota bB?

It sits in a horizontal slot behind the glovebox. Lower the glovebox, remove the small rectangular cover on the HVAC case, then slide the filter out and in. No tools are normally required.

What part number or type should be used?

Toyota’s EPC lists the cabin filter element as 87139‑52020 for NCP30/31/35. Activated‑carbon versions are available. Always verify by VIN or compare the old filter’s dimensions if fitted.

How often should it be replaced in Australia or New Zealand?

Every 12 months or 15,000 km is a good rule of thumb. Replace sooner if you drive dusty roads, park under trees, or notice reduced airflow, increased fan noise, foggy screens, or musty odours.