
Okay I'm back again & I seem to be getting somewhere.
1st step must be you checking whether you have a bulb issue or other ( possibly LCM issue). As said you can swap around the small side indicators in the front wings. Be careful not to mix them up. If right bulb works in left unit then it's the problem may be other than bulbs..............In an ideal world you will merely find you have 2 defective bulbs.
I have just been out to mine, (not for 1st time today), & removed one of the small side indicators. I can confirm that when removed the front and rears still flash at the normal interval & the green dash indicator lamp does not increase in illumination frequency. Thus it is possible that you could have 1st had a defective side indicator but not been aware it had failed in abscence of physically checking or viewing the lamp in operation. Only when one of the front or rear indicator bulbs fail would the frequency of the dash display increased.
In a less than ideal world you may be looking at needing a new Light Control Model. I have looked up parts on realoem. link here. Which exact unit will depend on what headlamps are fitted to your car. The bad news is the cost of 523.67 USD.......I will leave you to do the sterling currency conversion if I may. Obviously on top of that there would be the labour to fit swap out old for new, ( negligible labour to swap as it's relatively easy to get to if situated in the footwell). Finally there's the issue of programming the unit. I don't know how a main dealer would charge for this. I know in past there has been deliberation from folk re what labour should be charged if a car is merely be hooked up to a dealer computer for hours rather than being physically worked on during that same time.
I hope this helps...........I need to get ready for work now.
Good Luck