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Speedometer runs in reverse

After I replaced my battery the speedometer runs in reverse, why would this happen?





















































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I recommend you remove the reverse idler gear…then it will run in the proper direction.

What kind of car, year make and model?

Most modern cars have a VSS (vehicle speed sensor) that sends the computer a signal to let it know how fast the car is going. The computer then relays the signal to the electronic speedometer in the dash. I suggest that you disconnect the battery, and let it sit for 30 mins. before hooking it back up. See if this resets the electronics.