DTC U2151: Navigation Display Serial Data High/Low Circuit: Description

WARNING: This page is about a different car, the 2001 Cadillac Seville. However, it is still accessible from the selected car via links, so may be relevant.

Navigation display head (NDH) communicates with Navigation Module (NAV) over 2 dedicated lines. These are navigation display serial data high and low circuits. DTC will store when NDH does not receive a command from NAV after 15 seconds. When DTC is stored, display does not update or change function or screen may become blank. A message of LOSS OF COMMUNICATION WITH NAVIGATION PROCESSOR may appear on display. DTC will clear when NDH receives a response from NAV.