so i have been fixing my n/a s5 gtu, i recently replaced my eomp and all that is left is replacing the ecu which is on its way. i just need to know where to locate the main ecu in a second gen. god i hope this finely gets my car out of limp mode. please dont flame im new to rx7

 

On my S4 T2 it's in the passenger footwell. I can't imagine they moved it in the S5.

 

S4 coupe and S5 vert I've had, they were both under the passenger floor as well. Pull back the carpet and you'll see a metal plate, unbolt that and the ECU is underneath.

 

awesome thanks a lot