Some mb dealers say they change oil and filter and air filters and cabin filter but they dont they charge you for this service this happens alot in florida

"B" in the maintenance area means a brake service needs to be done.
"1" is a tire rotation.
"2" is cabin air filters needs replaced.

replace the timing belt , crank and cam shaft seal , hydraulic belt adjuster and idler pulleys ( 100,000 km limit)
rest of the service as per the service manual
if automatic . change the auto oil and if CV Transmission check with the dealer as the transmission oil to use as it is different to automatic oil

I'm pretty sure that there is no electronic devices around the cabin filter. The only thing that might be making that noise is the little door that keeps the filter in place. Make sure its closed in properly

I was recently changed the cabin filter on my TL 04, i don't think it necessary, it is more like optional but if you change filter for your engine, why not change the air you breathe inside the car. After i change my cabin filter i noticed more air are been circulate through out and also fresher than before. the price for a cabin fiter is also relatively cheap less than $10. took me 15 mins to do it. check it out at http://www.youtube.com/watch?v=FQsDxqxyeqM

There is not much maintinace on these, the trany oil doesnt and should not be touched maybe at 100,000 miles, at 60,000, rotate tires, change oil, check and replace air filter if needed, change cabin filter, and the rest is checking fluids, brakes etc, theres not much the most necessary thing is the oil change and rotate tires, i know the dealer charges alot for nothing, youcan look in the manually in the rear it shows you the services, or just google the year make and model and maintinance required. and it will also show you, good luck hope this is helpful.

It's under the dashboard. First you must dismount the accelerator pedal (!), remove some dashboard plastic on driver side. The filter is somewhere behind the central console.
I think it should be changed every two years. Look into the manual.
The company where you take the car for oil & filter change every year must change also this filter with no additional charges. Of course they charge you for the filter, which is not very exponsive.

they are @ $25 on ebay.

your behicle did not come with one from the factory.

SECTION 412-01: Air Distribution and Filtering 2001 F-150 Workshop Manual
DESCRIPTION AND OPERATION Air Distribution NOTE: A cabin air filter is available as a dealer installed accessory for the air distribution system of this vehicle. The instructions for installation and servicing of the cabin air filter are included with the filter when purchased.

It's under the dashboard. First you must dismount the accelerator pedal (!), remove some dashboard plastic on driver side. The filter is somewhere behind the central console.
I think it should be changed every two years. Look into the manual.
The company where you take the car for oil & filter change every year must change also this filter with no additional charges. Of course they charge you for the filter, which is not very exponsive.

What was the weight of the oil that was put into the engine when it was changed? Prius engines are VERY PICKY about the proper weight of the engine oil. Trust me. I see this quite often. The wrong weight oil can do bizzare things, and def lower your mileage. Something you can check: Take off the tube leading to the throttle body, and look down into the intake. Do you see any oil laying in the intake manifold? If so, you DEF have the wrong weight oil. This will NOT set a Check Engine light, either. Hope this helps.