I don't have this model but understand many odometers, like mine, reset the wheel size to wrong setting when battery replaced. Go to setup screen to reset to correct value. Setup screens normally appear if buttons held for about 2 seconds or more. Some models require millimeters and some centimeters. If you don't have a figure for your tyre measure the distance on the ground for one complete revolution of the wheel.
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I don't have this model but understand many odometers, like mine, reset the wheel size to wrong setting when battery replaced. Go to setup screen to reset to correct value. Setup screens normally appear if buttons held for about 2 seconds or more. Some models require millimeters and some centimeters. If you don't have a figure for your tyre measure the distance on the ground for one complete revolution of the wheel.