Lighting and/or signalling device comprising an optimised adjusting mechanism

The device (1) has a support (2) and a light unit (3) that is mounted in a swiveling around an axis (15) with regard to the support. An adjusting device (28) is arranged for adjustment of the light unit with regard to the support. The adjusting device includes a shaft (13) on which a threading (21) is placed. The shaft extends according to a direction (14) orthogonal to the axis swiveling with regard to the support. The light unit includes a confrontation that cooperates with the threading of the shaft. An independent claim is also included for a method for assembly of a lighting and/or signaling device.