Checking of the Cooling Fluid Level

Quick facts :

• Quantity : 16 litres.
• ...in progress

Gathering infos on the subject here ...

RR Forum (Brian) : The coolant should be very close to the top "fill opening" on the header tank.
The bit in the middle is the coolant level sensor. There are two probes that must both be submerged in the cooling fluid in the header tank to keep the low coolant light from illuminating.
I was never picky about the exact level. So long as there's enough in the header tank to keep the warning lamp from illuminating you've definitely got more than enough coolant.

Have a quick look at this link