Originally Posted by tabetha

Most likely the self canceller is broken, this is a ring around the steering column, under the wheel that has a protrusion on it, that physically pushes the indicator foot back in, when you indicate a "foot" type bit pokes out this gets knocked back in as the wheel is straightened after the turn, the self canceller bit often breaks, easy job though and cheap, just beware to let airbag de energise for 10 mins if fitted before unplugging(after disconnecting battery).
tabetha