temperature warning light

[bob at cemetery.homeunix.org (Andrew Basterfield)]

Hello

Driving flat out uphill today the warning light in the temp gauge
started flashing even though the gauge was only reading half way. I was
about 85 miles into a 90 mile trip home so I backed right off
thinking I may have done some damage and and light went out but then it
flashed occasionally for the rest of the journey, mainly when I was
accelerating. The gauge never went above half way.

Is the warning light sender the same as the gauge? Is this likely to be
a minor electrical gremlin or an overheating problem?

Andrew