Spedo Needle

Caused by voltage spikes. Drive over half the speedometer's maximum reading to bring it down. The pointer is not the spring-loaded type that worked fine for decades. It has four coils of wire that are pulsed by the computer within the instrument cluster to set the needle to the desired position. When stopped, the needle looks for the shortest way to "0", and if it has jumped up over half way with the ignition switch off, the shortest way to zero is backwards.

Your mechanic can also use the Chrysler DRB3 scanner to run the gauge test sequence. That will run all of them up and back down. As a last resort, you can pull the lens off and push the pointer back down.

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