thermal time switch testing (450 SE)
 

I have 2 Mercedes- a 74 450 SE and a 75 450 SE both with electronic fuel injection. the 74 starts cold easily. When I pull the thermal time switch plug on it and do a continuity test across the two terminals the multimeter does not beep when it is cold.
When I do this to my 75 cold that doesn't start easily cold, there is a "beep" on the multimeter. Of course I thought I had identified
how to check the switch. The new thermal time switches have been back ordered so I grabbed 2 out of junked cars. To my dismay they both activate the multimeter continuity check beeper.
I know there are ways to test resisitance etc. but for a simple continuity check can anyone tell me (maybe by pulling the plug on their car) whether a working thermal time switch will "beep" a multimeter on continuity when it is cold.