I THOUGHT I had caught out Renault over its ingenious 'Renault Card', which takes the place of a conventional key.

The card, about the size of a credit card but a couple of millimetres thick, had become increasingly reluctant to unlock the car when the button was pressed. Several harder presses brought success but, I thought, what happens if it fails to unlock the car?

Examination showed the card holds a concealed key - but (polite answers please) where does one put it? A look around the car, including the obvious places like door handles, failed to reveal anything resembling a key-hole.

Time to consult the handbook (too late if you're already locked out and the book is in the vehicle). All was revealed: the nearside front door handle has a cover which is removed by prising it off with the key.

Next question: if the battery in the key was flat, will the engine start? Those clever people at Renault have prepared for that and supplied a spare battery in the vehicle wallet. So all's well that ends well, with the moral of this little episode being to read the handbook as soon as you get the car.

Anyway, back to the test. Really, there is not a lot to add to my colleague Trevor Gelken's last report. Trevor's fear of hi-tech regarding the £1,500 sat-nav option might have been well-founded. I usually like to fiddle with these things and most of the time they are quite easy to fathom out.

And so it was with the Laguna - except for one occasion on a trip from mid-Bedfordshire to the wilds of Norfolk when it steadfastly refused to sort out the route.

It did redeem itself, though, when it suddenly decided to snap into life about 10 miles from journey's end, just when we needed it. Perhaps the satellite was being serviced!

What impresses me most is the refinement of the common rail diesel engine, the comfort of the sports seats (although they take a bit of fiddling to get exactly right) and the car's superb fuel economy.

I took over the Laguna with the fuel gauge showing a quarter full. Must fill up soon, I thought, while having a quick flick through the onboard computer's functions to arrive at the distance remaining before the tank was empty. Surprise, surprise, it showed a range of almost 200 miles. And the needle seemed reluctant to move towards the red.

The car is averaging 48mpg but on a regular 50-mile journey the computer has indicated an excellent 53.3mpg, demonstrating the usefulness of a six-speed gearbox. It is a nice feeling to see that you have a range of nearly 700 miles after a fill-up.