We have a couple of 89's, one a wagon, the other a 4-door.

The battery for ignition arrives at the coil on the blue wire. Like Chuck says, the blue wire originates at the ignition switch (circuit 15) and appears on the hot side of the fuse block. It does not get fused, but leaves the hot side into the wiring harness bundle going through the firewall to a connector close to the coil, here:



I've had the experience of repairing the connector for corrosion in two cars, strangely neither of them were our cars.

But until just this year I would have never suspected the wire itself could be a problem between that connector and the fuse panel. In our sedan, the tach stopped working. Some rodent, either mouse or squirrel, chewed into the harness where it passes under the left strut tower. Got the white/red wire, not the blue one next to it. Difference between tach not indicating and car not running depended on the rodent's choice of wire.
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Art Benstein near Baltimore

“How much does a chimney cost?”

“Nothing, it’s on the house…” or "It's gone through the roof..."