Hi, I take it other than the light the fridge is working as expected, its getting cold and you have no other issues?
Assuming the fridge is working in all other respects, to diagnose further you need a multi meter, to test if your getting voltage to the bulb socket.These type of faults are generally caused by the door switch or corroded terminals in the bulb holder.
Give the door switch a goog wiggle and flick it in and out to give it a chance to come back to life, its unlikly to cause any damage if it isnt at fault. Next remove the bulb and have a look inside the holder does it look clean
Thanks I purchased a mega meter and tested the switch (which was faulty). And therfore covered under the manufacturers warranty.
Thanks for your assistance with