If you want to know what the weather will be three days from now or whether there's an accident three blocks from here, the 2009 Acura RL is at your service.

Its sophisticated electronics will pinpoint construction hot spots, keep tabs on average speed on the route home so you can find a quicker alternative, provide outside temperature readings and odds for rain or snow, furnish an indash calculator so the kids can do homework or mom and dad can do their banking, and offer the latest Zagat restaurant ratings for those who don't place their orders with a plastic clown.

RL is the flagship of the Acura line, a car loaded with electronic wizardry for those to whom transportation is more than how many miles you can get out of a gallon.

The RL has undergone considerable change for 2009--new hood, grille, fenders and tail end as well as an upgraded cabin and a 2-inch stretch in length. But even with all this, styling is typically Japanese vanilla. Only the chrome logo lets you know it's an Acura.

We tested the top-of-the-line RL with Technology Package and Collision Mitigation Braking System, or CMBS, as well as adaptive cruise control, or ACC. If you get too close to the vehicle ahead, ACC backs off the throttle and/or gently applies the brakes to keep you at a safe distance.

Great system with one drawback: You have to engage cruise control first. CMBS takes that to a higher level by preventing a collision without cruise control engaged. Come up on a vehicle too quickly, and CMBS sends an audible warning. If the beeps are ignored, it gently tugs on the safety belts. If the tugs don't work, it applies brakes, though not fully. By then you should have gotten enough hints you're going to crash to slam 'em yourself. A button on the dash shuts off CMBS, though why anyone would push it is a mystery.

The RL holds four adults comfortably. The amply cushioned seats mold to your body to hold you in place. And the perforated leather not only prevents slipping or sliding, but also provides heating and cooling. While toasty seats are great in January, cooled seats are even better in August.

The ride is smooth, handling secure. Twisties are no challenge.

Stability control is standard along with full-time all-wheel-drive that directs torque front to rear or side to side when wheel slippage is detected to maintain traction. All-season maneuverability.

RL also comes with active front lighting that directs headlamp beams in the direction of a turn to better see what's ahead, and a backup camera to show what's behind when going in reverse.

Other nice touches include keyless start, a power plug in the console that stays hidden until you need it, a USB port and another power plug under the center armrest, a compartment for the owner's manual in the glove box, though that will render invisible a book that's least likely to be read. There's also a button that allows the 12-ounce cupholder to accommodate that 64-ounce Big Gulp and voice activation for up to 70 items, though we couldn't get a word in with about 68 of them.

A rear-window sunshade powers up or down, as do the rear headrests for clear vision when no one's there. Lower the rear-seat armrest to expose a ski pass-through from trunk to cabin. The trunk has very good room for luggage and gear, plus plastic grocery-bag holders in the sidewalls and hooks in the floor to secure items.

RL is powered by a 3.7-liter, 300-horsepower, 24-valve V-6 that replaced a 3.5-liter, 290-h.p. V-6. It's teamed with a 5-speed automatic with manual mode paddle shifting. The V-6 is energetic yet very smooth and quiet.

The mileage rating, however, is only 16 m.p.g. city/22 m.p.g. highway. A V-6 that shuts off 2 or 3 cylinders when not needed like on the Pilot SUV would help.

But Acura skips it because its owners haven't asked for it-even though Acura V-6 recommends premium unleaded. Regular is OK, but you'll sacrifice some horsepower.

The RL tested starts at $53,700 with no options; none are needed. One car's goodies-power moonroof, power-heated mirrors, satellite radio, Bluetooth phone, navigation system, climate control, rear-side-door sunshades and side-curtain air bags-are RL's standard gear.

Read Jim Mateja Sunday in Transportation. Contact him at transportation@ tribune.com.