406 hdi engine auto diagnostic light

You need to get it plugged into a computer.

First place to look would be the glove box.

Rob J

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Rob Jones" saying something like:

Might be anything. Stick a piece of black tape over it.

Without a scanner you cannot be sure, I have just bought a £4000 Snap-on Solus because i'm fed up with guessing.

Hopefully it will contain the owners manual, which will tell you what the light means, and what you should do when it is lit.