Navigation System - Vehicle Position Indicator Inoperative or Erratic

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

Step	Action	Yes	No
Schematic Reference: Radio/Navigation System Schematics Connector End View Reference: Entertainment/Communication Connector End Views DEFINITION: When using the navigation system, the vehicle position indicator does not operate or is erratic.
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Start the vehicle and press the NAV button to switch to the navigation screen. Drive the vehicle for longer than 15 seconds with the speed above 15 mph. Monitor the vehicle position indicator. Does the vehicle position indicator operate normally?	Go to Testing for Intermittent Conditions and Poor Connections	Go to Step 3
3	Test the Vehicle Speed Signal circuit for an open. Did you find and correct the condition?	Go to Step 6	Go to Step 4
4	Inspect for poor connections at the harness connector of the navigation radio. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 6	Go to Step 5
5	Replace the navigation radio. Refer to Control Module References . Did you complete the replacement?	Go to Step 6	-
6	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2