MX5 brake warning light

[KaraokeMidget]

I recently got into hairdressing and bought a Mk3 2006 2.0 sport MX5.
It was owned by my father-in-law who drove it at 40 mph everywhere.
Now I gave it a blast recently but around 70-80 mph the handbrake/brake red warning light came on steady. I eased off a bit and the light went off.

Any suggestions.

Also looking a small bit of rust removed on the rear wheel arch is anyone can recommend someone in the Ards/Bangor area.

 

[PeteMoore]

Fluid needs topped up

 

[KaraokeMidget]

Fluid needs topped up

Check that this morning and it is fine.
The thing that bothers me is that it comes on around 70 mph without me braking. If anything I am still accelerating

 

[Cob]

Definitely brake fluid needs topped up to the max mark.

A very common thing on mk3's. A few ml's below max is enough to set off the sensor.