FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Speedometer and/or Odometer Inaccurate or Inoperative




Speedometer and/or Odometer Inaccurate or Inoperative

Diagnostic Instructions

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

Circuit/System Description

The instrument panel cluster (IPC) displays the vehicle speed based on the vehicle speed information from the engine control module (ECM). The ECM sends the vehicle speed information via the serial data circuit to the body control module (BCM). The BCM then sends the information via the serial data circuit to the IPC in order to display the vehicle speed and accumulated miles traveled.

Reference Information
Schematic Reference

Instrument Cluster Schematics (Instrument Cluster Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Instrument Cluster Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, perform the speedometer sweep test with the scan tool. Verify that the speedometer sweeps from its low to high position.

If the speedometer gage does not sweep from its low to high position, replace the IPC.

2. Ignition OFF, raise the vehicles drive wheels.
3. Engine ON, transmission in drive or 1st gear, verify the scan tool Vehicle Speed Sensor parameter matches the speedometer display.

If the Vehicle Speed Sensor parameter does not match the speedometer display, replace the IPC.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for IPC replacement, setup, and programming