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I've never dicked with quad drivers. Yes, that could be the problem with your electrical accessories not working. Kinda depends on whether the failed QD activate those accessories. I'd expect that to be in the service manual; wiring diagrams probably--but I've never needed to look that up. I suppose you could solder new QD into the ECM, but it's probably easier to replace the ECM and see what happens, AFTER you assure that those accessories aren't drawing excess current. Kinda guessing the QD turns on a relay, which turns on the accessory. So it'd maybe be problems in the wire harness to the relay, rather than the accessory itself.

Generally a quad driver issue showing on ones scanner is due to a possible short in the circuit that the quad (transistor) is controlling. The *failed* quad is the result of the issue not the source. One needs to test the circuit the driver is controlling for opens or shorts. The PCM is not necessarily the root problem.

In the absence of any further information, what i would do is manually either trigger the relays for the fan or remove the relay and jump it that way. just to see if the fans work. It would be great if you had a tool that could command the fans on, but alas. the next best thing you could do is prove either the relay socket or probe near the PCM when the car should be commanding the fans and verify that. That all said, I cannot base this on anything short of "but I remember this being an issue back when on the forum" but I seem to remember people having issues with QDMs on the 94/95 PCMs I believe Schurkey is on the right path about the QDMs being what provides power to the relay in order to trigger it.