How do you reset an odometer. Odometer not working.
Most likely the plastic gears that drives the odometer section of the speedo has broken. Inside the speedo there is a worm drive gear on a shaft and a larger gear runs off that to drive the odometer part. That gears has a tendency to crack which causes it to either fall off the end of it's shaft, or sit there turning but not turn. Check the transmission end of the cable as well.
First off, Saab doesn't use any mechanical means to determine speed. It uses a wheel encoder to the ABS computer to the Main Instrument Unit or speedometer/odometer. With a Tech II tool connected to the car ODB-II port under the steering wheel, the wheel diameter could be set to a larger wheel which would speed up the car to the speedometer higher readout. That's about the only way.
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