The auto function only works when the light level is low enough,and should come on when you go into a tunnel,or underground car park.
On my Renault when the lights are switched on,you press a button on the end of the light stalk,and a message is displayed on the computer,confirming the auto light function is enabled.
Read your handbook to check method of activation.
Failing that the light sensor which triggers the lights may have failed(unlikely)
doug sinnott, October 2009
