I just hooked up a shift light in my car and it is not working right. I have a good ground and positive connection and I have it hooked up to the negative side of my coil. When I turn the car on, the shift light turns on and shuts off like it is supposed too, but it won't turn on with my 3000 test pill. I have the setting on the back of the light set to 8. I do have an MSD in my car, but I should still be able to hook it up to coil right? Any ideas???