On Friday, April 10, 2015 at 7:35:10 AM UTC-4, Martin Gregorie wrote:
ASI check. My pitot is a fairly large metal tube sticking out of the fin-
about 12mm diam and 120mm long with a hemispherical end and 3-4mm hole in
its centre. I put my thumb over the hole and then close my hand around
the tube. If the ASI doesn't go up to about 20 kts and stay there until I
let go, I know there's a problem. The exact reading depends on the day
temperature because what makes the reading go up is the pressure rise due
to my hand warming the pitot probe.

TE check. With a vario on and volume fully up, I put a flat hand on
either side of the TE probe and blow hard between my hands. If the vario
yelps I know the TE connection is good.

The above checks will not catch water in static,
nor leak in TE connection, nor leak in statics,
nor pitot plugged by bugs, all common problems...

Hope that helps,
Best Regards, Dave