what is the little black box on a renault megane gearbox called?

hope all this info helps. going by the haynes manual, the switch is the - multi function switch. DPO switch. but does what the two previous posts say. And yes you do the setting when it's in neutral.

sim
April 2010

Its not the electric control unit as the other post states . It is the transmission range sensor/switch. The 2 spade terminals are to adjust the switch. In 'N' there should be continuity across terminals.

mags
April 2010

this is the electronic control unit that enables gear selection. the spades are points to check with a multi metre the correct setting. i think 0.03 ohms?? if memory serves me correctly. had experience with this unit. my father has same car as you, and has gearbox issues. going into limp mode, then no gears whatsoever etc. changed this box. set it as described. changed gearbox internal relay/solenoids (2 of em)....finally got 2gears selected.3rd and 4th, ah well it's sort of a result as it drives now!!!

sim
April 2010