B0001

DTC B0001

Circuit Description

The navigation radio receives the vehicle speed signal from the powertrain control module (PCM) through a dedicated circuit shared with the instrument cluster.

DTC Description

This diagnostic procedure supports the following DTC:

DTC B0001 Vehicle Speed Information Circuit Range/Performance

Conditions for Running the DTC

* The navigation radio must detect a power mode transition to ON.
* The radio does not set this DTC if B1327 or B1328 is current.
* The vehicle must drive for 2 miles after receiving a global positioning system (GPS) signal.

Conditions for Setting the DTC

The navigation radio compares the vehicle speed signal from the PCM to the GPS data. If the GPS signal indicates that the vehicle has traveled 2 miles but no vehicle speed signal was received, the radio sets the DTC.

Action Taken When the DTC Sets

The navigation radio uses the GPS signal when the vehicle speed signal from the PCM is unavailable.

The following symptoms may happen if the vehicle speed signal from the PCM is unavailable:

* The vehicle icon may jump to different positions on the map screen.
* The vehicle icon, current position marker may not move on the map screen while the vehicle is being driven.
* The route guidance accuracy may be degraded.

Conditions for Clearing the DTC

* A current DTC clears when the navigation radio detects the vehicle speed signal from the PCM for more than 1 second.
* A history DTC clears after 50 ignition cycles without a vehicle speed signal failure.

Diagnostic Aids

An intermittent condition may be caused by the following:

* Misrouted harness
* Rubbed through wire insulation
* Broken wire inside the insulation
* A loose connector pin

Test Description

Step 1 - Step 6:

The numbers below refer to the step numbers on the diagnostic table.
1. Determines if the malfunction is present.
3. Tests for an open in the vehicle speed signal circuit between the cruise control and the navigation radio. A short would cause the cruise control to malfunction as well as the navigation system.