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Proble with L293D H-Bridge


My L293D H-bridge no longer works.
I isolated on a mounting plate so is is not disturbed by the rest of the circuit and it still does not work
Can anyone confirm that my test is correct:

Pin 1 (enable 1) and pin 2 (Input 1) and pin 8 (VS) connected 3v arduino
Pin 16 (VSS) connected 5V arduino
4,5,12,13 pin (GND) and pin 7 (Input2), pin 9 (2 enable), pin 10 (Input3), pin 15 (INPUT4) connected to ground arduino

Under these conditions, I will measure 5V on pin 3 (output1) but the pin is still equal to zero volts
My test is it correct ?

thank you

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yes you are right, 3V is too low.

I have connected to 5V and it works now

thanks a lot !

Have you got a common gnd between all your devices? Beats me why you want to use 2 different arduinos to control the L293D. Thats just asking for trouble especially when one is a 3v and the other a 5 volt.
I think you'd better rethink your circuit to run the h-bridge with just one of them unless you can give me a good reason for this setup.