What is this panel light?
 

It comes on when I press-to-test. It doesn't have a label and it wasn't labeled in my POH. It's circled in red below my turn/bank indicator.

Jim,

I have two push-to-test lights on my panel. One is for the turn and bank indicator, the other is a "hydraulic system-gear in transit" light.

Kevin

Light
 

Looks like Turn and Bank test light.
Jeff

My guess is that it is the T&B test light. I think it is there as not all electric T&B have a power supply indicator.

Makes sense. My T&B has a built in flag, but I guess the original didn't.

Thats your combustion overtemp light
 

I believe that is the combustion heater overtempt warning.

To confirm, on my T337, that lamp comes on briefly when you move the combustion heater switch to RUN, then goes out once the heater is started.

It will come on if the combustion heater over temps

Label
 

Mine has a label on it which says - " T&B Test Push" Must be Turn and Bank test

Everyone's right.

It IS in my POH in a text paragraph, even though it's not identified on the panel diagram. It is NOT labeled on my actual panel.


From my POH, Page 2-7:

TURN-AND-BANK TEST/HEATER OVERHEAT INDICATOR LIGHT

A dual-purpose amber light, labeled "T&B TEST - HEATER OVERHEAT," is mounted directly below the turn coordinator or optional turn-and-bank indicator. When depressed, the light will illuminate if electrical power is being supplied to the instrument. Illumination of the light, without manually depressing it, indicates a combustion heater overheat condition.