- that the upper spring pin (21) is in tension in the groove of the control rod (9) - That the spring (22) embeds itself in the screw locating spring to prevent slip - that the headlamp unit, when disconnected from the control rod, pivots freely. (if not, check the of the leads and wiring connectors, which may foul the housing). - that the points of the lower springs (22) and (25) press on the headlamp unit flange.