Brake liquid level

Lights set, CO was ok right from the beginning (lambda control seems to work fine), bushing was a tight fit... but it was supposed to be, there was something left called BRAKE FLUID RESERVOIR LIQUID LEVEL INDICATOR CONTROL LIGHT ! To cut a long story short, if they want to check for the level at tech control, the reservoir normally has to be transparent. Since my car has solid aluminium reservoirs, I added a control light for the level indicators. The test button serves to check wether the bulb works or not. Fingers crossed for tech control on Friday!
Cheers.