I have a 1.6 Vauxhall zarfia 1999 and sometimes a Amber em light comes on and stays until I switch the engine off . When I switch it back on its gone . It seems to come on when I am doing 50mph/higher or when driving on bumpy roads but it's not all the time it's ever now and then .
The first thing to do is to get it onto a code reader to see what faults are stored and work from there,nigh on impossible on modern motors to do otherwise unless you want to guess which can cost a lot of money,good luck.