[denisond3]

I think I would find the PCM, disconnect its 'connections' to the car, and see if the grounded wire is still grounded, or if it was a problem in the PCM. If its a bad wire, I might try disconnecting the wire from the bundle going to the connector on the pcm, and splice in the IAT sensor right at the PCM (to eliminate a shorted wire somewhere inside a bundle under the hood or dashboard). If the SES sees the more or less correct resistance of the IAT, it should at least agree to let the SES light go out.
It may take some driving time before the SES light goes out.

I 'think' the PCM is in the center console, sort of behind and below the radio, but Im not near my Saturn manual. Nor do I have any wiring diagrams that I can refer to. Sorry.
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