I have a 1999 xj 4.0 4wd aw4. With the key in run the asd relay buzzes, the electric fan turns on and off repeatedly for no more than a few seconds, the fuel pump primes over and over. The Jeep will start if I give it gas and manually keep the rpm’s high until it’s been driven for a few minutes. Afterwards it will shut on and off fine until it cools down. Then I have to start over and make it start. I was going to do more troubleshooting before I made a post but I’ve ran into something interesting, I have a running 98 xj so I swapped the asd relay from that into the 99 and vice versa. The 98 still runs fine and now the 99 gives a NO BUS on the dash. So far I’ve verified 4 good relays, all work fine in the 98 with no symptoms and 3 give a no bus in the 99. Only the one original asd from the 99 will buz and give a start condition.

 

After checking everything and going through every post on every forum about the asd it turns out it’ll buzz and display “no bus” if your fuel pump relay fuse has a bad connection.