The way I know to see if the amplifier module is working is to put a test

light on the side of the coil that it switches (-)and see if it flashes the

test light. If not, and the unit is getting a signal from the ICU then it's bad. I only had to trouble shoot this system once. In my experience

with electronics you always consider the items that get the most stress in

the system first. That would be the rpm sensor, and the amplifier. When I

had to trouble shoot the 90 wagon in our family the rpm sensor was the culprit. They can be intermittent so personally the rpm sensor is always

the first part I would suspect. I haven't ever heard of a bad ICU. I guess

it could happen but judging by the price it's obviously rare that they

go bad.

I recommend putting dielectric grease in every connector you can find

on the motor. It will keep the corrosion at bay much longer.

Dave 82 242ti