Conditions for Setting the DTC
WARNING: This page is about a different car, the 2004 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
The navigation radio compares the vehicle speed signal from the PCM to the GPS location signal every second. If the GPS signal indicates that the vehicle has traveled 4 km (2.5 mi) but no vehicle speed signal was received, the radio sets the DTC.