DTC 12: Operation Signal To Speedometer
WARNING: This page is about a different car, the 2002 Mazda MPV. However, it is still accessible from the selected car via links, so may be relevant.
Wait for 2 seconds after selecting DTC 12. If speedometer needle moves full scale and then rests at 37 MPH (60 km/h), speedometer is okay. If speedometer needle does not move full scale and then rest at 37 MPH (60 km/h), replace instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION.