GM Service Manual Online
For 1990-2009 cars only

DTC B2461 RHD

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category

DTC Descriptor

DTC B2461 00: Navigation Electronic Control Unit (ECU) Synchronous Signal Error

Circuit Description

The navigation interface module (NIM) communicates with the navigation module via serial data. The NIM can request diagnostic information from the navigation module, if the NIM does not receive a response from the navigation module a DTC will set.

Conditions for Running the DTC

The ignition or the infotainment unit is ON.

Conditions for Setting the DTC

When diagnostic information is requested from the navigation module by the navigation interface module (NIM) and a response is not received.

Conditions for Clearing the DTC

A history DTC clears after 50 fault-free ignition cycles.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Navigation System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Disconnect the navigation gateway module and the navigation module X3 harness connectors.
  2. Test for less than 5 Ω between the following pin locations:
  3. • navigation gateway module terminal 1 and navigation module terminal C7
    • navigation gateway module terminal 7 and navigation module terminal C8
    If greater than the specified range, test the circuit for a short to ground or an open/high resistance..
  4. If all circuits test normal, replace the navigation module.

Repair Instructions

Perform the Diagnostic Repair Verification.

    •  Navigation Map Disc Player Replacement
    •  Control Module References.