T5 0.6w although 1.2w give a brighter light
the light tells you that you have passed its service interval
NO
To change the dash light bulbs on a Citroën Picasso, first, ensure the vehicle is turned off and disconnect the battery for safety. Remove the dashboard panel by carefully unscrewing or unclipping it. Locate the faulty bulb sockets, twist them counterclockwise to remove, and then replace the old bulbs with new ones. Reassemble the dashboard and reconnect the battery to complete the process.
It's under the n/s front light.
Take the gearbox out and flip it round twice
The alternator needs attention or replace
if is xsara picasso then: from inside move carpet on the left side, there you see two metal parts which need to be squeeze and all rear light come off. Then you take off plastic where are all bulbs in, brake, direction and reverse bulb
Bad light bulbs.... Replace them...
ABS Brakes need servicing.
Check fuses and light bulbs
you have to remove the cover of the dashboard to replace the light bulbs