how do i turn off the spanner symbol and reset the service counter on a peugeot 307 sw (02 plate)

You need a special clip that plugs in the OBD connector.

Or, how about getting it serviced?

Not sure about a peugeot but on a ford its behind the glove box. A little button and the light goes out!

you will need the plug in computer code reader that resets the on-board computer, alternatively, you can use a paperclip to short out the sender unit, but l would NOT recommend you try this unless you are competent and know exactly which sender unit you looking at. l use this method on my vectra sri and it works for me.hope this helps dude.

Here goes:

1. Press and hold trip counter reset button(left of speedo)
2. Switch ignition on
3. Keep pressing trip reset button for 10 seconds
4. Display will now read 0 and spanner symbol will go out.

Hi there
Tim R has it right!! once you hold the button to the right of the display turn on ignition and the display will count down to 0 from 10 once it reaches 0 release the button and the indicator will be reset.
Cheers