XL-7 2WD V6-3.6L (2007)
Speedometer Head: Testing and Inspection
Speedometer and/or Odometer Inaccurate or Inoperative
Diagnostic Instructions
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Perform the [Diagnostic System Check - Vehicle Diagnostic Information] prior to using this diagnostic procedure. See: Testing and
Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System Check - Vehicle Diagnostic Information
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Review [Strategy Based Diagnosis] for an overview of the diagnostic approach. See: Testing and Inspection/Initial Inspection and Diagnostic
Overview/Strategy Based Diagnosis
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[Diagnostic Procedure Instructions - Vehicle Diagnostic Information]. See: Testing and Inspection/Initial Inspection and Diagnostic
Overview/Diagnostic Procedure Instructions - Vehicle Diagnostic Information
Circuit/System Description
The instrument panel cluster (IPC) displays the vehicle speed based on the information from the engine control module (ECM). The ECM converts the
data from the vehicle speed sensor to a 4000 pulses/mile signal. The ECM sends the vehicle speed information via high speed GMLAN serial data circuit
to the body control module (BCM). The BCM then sends the information via low speed GMLAN to the IPC to order to display the vehicle speed and
miles traveled.
Circuit/System Testing
1. Ignition OFF, raise the vehicles drive wheels.
2. Engine ON, transmission in drive, verify the scan tool Vehicle Speed Sensor parameter matches the speedometer display.
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If the Vehicle Speed Sensor parameter does not match the speedometer display, replace the IPC.
3. Verify that the odometer is operating properly. If the odometer is not operating properly, replace the IPC.
Repair Instructions
Perform the [Diagnostic Repair Verification - Vehicle Diagnostic Information] after completing the diagnostic procedure. See: Testing and
Inspection/Diagnostic Trouble Code Tests and Associated Procedures
[Control Module References] for IPC replacement, setup, and programming See: Testing and Inspection/Programming and Relearning
