Vehicle Position Wanders on the MAP
Vehicle position wanders on the mapNOTE:
- Always check the connectors for poor connections or loose terminals.
- Before troubleshooting, get the navigation system anti-theft codes.
- After troubleshooting, enter the navigation system anti-theft codes.
Vehicle Speed Pulse (VSP) Check
1. Test drive the vehicle.
Does the speedometer operate correctly?
YES - Go to step 2.
NO - Check the gauge assembly function by using self-diagnostic function.
2. Stop the vehicle with the engine running.
3. Perform the Car Status test under "Unit Check" in the System Diagnosis Menu.
Is the VSP indicator ON when the vehicle is moving?
YES - Do the yaw rate sensor check, go to step 12.
NO - Go to step 4.
4. Turn the ignition switch OFF.
5. Disconnect the navigation unit connector C (8P).
6. Check for loose terminal at navigation unit connector C (8P).
7. Reconnect navigation unit connector C (8P).
8. Raise the vehicle, and make sure it is securely supported.
9. Turn the ignition switch ON (II), and shift into neutral.
10. Connect a voltmeter to body ground, and back probe navigation unit connector C (8P) terminal No. 6.
11. Slowly rotate one wheel with the other wheel blocked.
Does voltage pulse from 0 V to about 5 V or more?
YES - Replace the navigation unit.
NO - Repair open or short in the wire between the PCM and the navigation unit.
Yaw Rate Sensor Check
12. Perform the start-up procedure.
13. Select Yaw Rate.
14. The yaw rate offset and sensor should indicate 1.500 to 3.500 V with the vehicle stopped. If either is zero or five volts (0.00 V or 5.00 V), replace the navigation unit.
15. The yaw rate offset and sensor should be within ±0.01 V of each other with the vehicle stopped. The sensor value should change relative to offset as the vehicle is turned while driving. If not, replace the navigation unit.
Example
Vehicle stopped:
Normal Abnormal
Offset 2.526 V Offset 2.526 V
Sensor 2.516 - 2.536 V Sensor 2.623 V
Vehicle turning:
Normal Abnormal
Offset 2.526 V Offset 2.526 V
Sensor 2.678 V(Right Turn) Sensor 2.525 V (no change on turns)
2.478 V (Left Turn)
NOTE: The next check will need to be done as the vehicle is driven, you may want to save this test until last. Have a helper monitor the screen as the vehicle is driven.
16. Select Tuning.
17. Test drive the vehicle on a straight section of highway. While driving the vehicle, monitor the RED ARROW SHAPED ICON on the "Tuning" screen. Just under the icon, you will see term "ANG-Disp" with an angle degree number written under it (for example: -4 °)
The icon will leave a trail of "BREAD CRUMBS" as it moves across the screen from left to right. It takes about 1/2 mile to cover the screen.
As you drive the vehicle the angle degree number should be 0 ° (±3 °). If after 1/2 mile the number exceeds 0 ° (±3 °), replace the navigation unit.
NOTE: This test relies on the vehicle being driven perfectly straight for 1/2 mile. If this is not possible, the results of this test will be false. When possible compare your results to a known good vehicle.