GM Service Manual Online
For 1990-2009 cars only

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 Descriptors

DTC B0550: Vehicle Odometer Information Invalid

Circuit/System Description

The ECM calculates the vehicle driven distance based on wheel speed sensor signal from the ABS module. The ECM sends the vehicle driven distance information to the steering column control module (SCCM) via the serial data circuit. The SCCM sends the vehicle driven distance information to the IPC via the serial data circuit. The IPC uses the vehicle driven distance data to calculate and display the vehicle odometer.

Conditions for Running the DTC

    • The engine is running.
    • The ignition voltage is between 9-18 volts.

Conditions for Setting the DTC

    • The ECM detects that the driven distance information is invalid.
    • The above condition must be present for a minimum of 8 seconds.

Action Taken When the DTC Sets

The ECM records the operating conditions at the time the diagnostic fails. The ECM displays the failure information in the Failure Records on the scan tool.

Conditions for Clearing the DTC

    • The DTC becomes history when the conditions for setting the DTC are no longer present.
    • The history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information

Schematic Reference

Instrument Cluster Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Instrument Cluster 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 Verification

  1. Ignition ON and the scan tool installed, verify that DTC P0550 is set as a history code.
  2. If not, replace the IPC.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for the IPC replacement, setup and programming.