2004 Chevrolet Impala Owner's Manual - Page 152

Speedometer and Odometer Your speedometer lets you see your speed in both miles per hour (mph) and kilometers per hour (km/h). Your odometer shows how far your vehicle has been driven in either miles (used in the United States) or in kilometers (used in Canada). Your vehicle has a tamper-resistant odometer. If you see ERROR, you'll know someone has probably tampered with it and the numbers may not be accurate. You may wonder what happens if your vehicle needs a new odometer installed. If the new one can be set to the mileage total of the old odometer, then that will be done. But if it can't, then it will be set at zero and a label must be put on the driver's door to show the old mileage reading when the new odometer was installed. Trip Odometer Your trip odometer tells how far you have driven since you last reset it. Your trip/select reset switch will go back and forth between the odometer and the trip odometer if the button is pressed and released within 1.5 seconds. If the button is pressed and held for longer than 1.5 seconds while in the trip odometer mode, it will be reset to zero. If the button is pressed and held for longer than 1.5 seconds while in the odometer mode, it will have no effect. Your trip odometer will work no matter what position your key is in, and even if the key isn't in. 3-30