Activate jack-out in speaker mode

Hello,

I'd like to use my galaxy S6 in hands free mode when i'm driving. My car isn't equiped with any car kit, i just have an audio input

When i connect my phone to my car stereo using jack output, i have two options :

• in standard call mode, i can hear people in my car speakers very fine but they don't because the mic level is very low (since i'm supposed to talk near to the mic)


• in speaker mode, jack audio output is disabled. so people hear me very fine (they don't hear ambiant noise) but i don't because audio comes from my phone speaker

My question is : is there a way to enable jack audio output in speaker mode ?

Thanks and sorry for my poor English