I was wondering if the s4 and s5 TII ECU harness for the engine were interchangable between each other? Basically the big plug that goes to the connecter in the ECU itself, is it the same between s4 and s5 TII ECU?

 

Largest S4 plug has 24 pins compared to 26 for S5.

 

Thanks. Exactly what I was looking for. I didn't know if there was any difference on the ECU side of the harness.