317. Using the trouble analysis chart and faults table provided in the illustrations, if the adaptive digital steering system was malfunctioning, and the fault code 42 (SPEED LOG ERROR) is displayed, what corrective action should be performed FIRST

The correct action for a SPEED LOG ERROR (fault code 42) is to first verify the speed log source and data strings, as indicated by the troubleshooting chart. This confirms the external data source is functioning before proceeding to wiring or module replacement.