'85 calibration PROM differences?


Sporadic Poster
The factory parts catalog shows one calibration PROM for the '85 G-body Hot Air, broadcast code CMM. But the listing says "FED", it does not say "FED,CALIF".

I know '85 Hot Air cars were sold in California (or more accurately, don't know that they weren't). Did the California cars come with this CMM calibration PROM, or a different one that for some reason got left out of the parts catalog?

You can tell by looking at the label on the fan shroud. It has the broadcast code in large letters, plus fine print stating what emissions the car conforms to. The chip itself also has the broadcast code on it (inside the ECM, under the little bolt-on door).

Thanks for any info. I know most people here have no use for the ECM, let alone the PROM, but this has been bugging me for some time.
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