Should be the orange light flashing and one or more green and/or red lights either steady for flashing, dependant on the fault.
Check in the manual:
http://pdfstream.manualsonline.com/d/dc489560-1c52-43e2-91ec-34b3030b2700.pdf
Look at page 32. that will show what does correspond to what lights flashing.
acp, April 2017
