If pcm fails to regulate voltage, can I rig an external
regulator to bypass pcm. Would the car run and
would it throw any codes for emissions testing.
The best repair is always find and repair the problem. You may make things worse by trying to "southern engineer" something, especially when computers are involved.
Actually they make kits designed to do just this, bypass the ECM voltage regulator when it fails. Some links: https://alternatorparts.com/external-voltage-regulator-high-output-alternator-kit.html ("External Regulator Conversion Kit for Your Chrysler, Dodge, Jeep. Gets the Voltage Regulator out of the Computer") - https://www.youtube.com/watch?v=HtB3g1kk8Rg
Well, that is news to me. Thanks for posting, Ken. I learned something today.
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