Doing remote start on a 88 xj and looking for the tach singal, that's if it goes to ecu. C5 is sync negative, C16 is sync postive, I'd rather steal a singal from the ecu if possible then going from the green white wire from the ICM. I've heard you can grab the singal from injector 1 which is B1. But I'm just not too sure.

 

Why not ICM?

 

I just didn't want to run a wire if I didn't have to just to grab the signal. I ended up just going under the dash and getting it at the tach. The more I was looking at the schematic I found it doesn't run the the ecu due to that it can cause interface.