1) Engine cranks, no spark : crank sensor or Hall sensor pickup in distributor (if it's an 89 Turbo I think it will still have the distributor pickup, instead of crank sensor)
2) Also possible the Suppression Relay has died- and they might have screwed around with that, since it's on the radio circuit. They might have burnt that up somehow. It's in the fuse box- see the 700FAQ for relay locations.
3) Spark but no fuel- Fuel Pump Relay or main fuel pump failure. Check fuse 1 in the fusebox too. Fuel pump relay is the big white one, front left of the fusebox. Has a date code on it- if it's over 6 years old replace it anyway.

Good luck, write again with what you find.
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Rob Bareiss, New London CT ::: 86 244DL, 87 244DL, 88 744GLE, 91 244: 808K total