12 volt ignition switch

I'm installing three electric fans in my 98 xj and I need an under the hood 12 volt switched by the ignition switch so the fans will turn off when I shut the motor down I was thinking the ignition coil but when I put a volt meter on both the wires on the plug I don't see no voltage I think it's computer controlled and the starter has to be cranking or the motor running does anybody know what color the hot wire is either green or black or maybe another ignition source

In the ECM on the drivers side, there should be a blue wire with white trace that is ignition controlled. I think it is in the connector pack closest to the driver. Use a volt meter to test it first.

Thanks man that worked it was I. The pack closest to the radiator but was simple enough to find