ECU diagnostic port doesn't work
My check engine light is on and when I connect the Actron to the port[it will not link. I do have an aftermarket stereo on my 97 D90, which the amplifier has been removed. I remember reading something about the ground to the amp was also the ground for the ECU. I have tried to groung the wires from the wiring harness to the amp I must not be doing it right. Any help would be appreciated-Thank you.