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Home >> Cadillac >> 2000 >> Seville STS >> Repair and Diagnosis >> External Pages >> Different car >> Section 216 (Cellular Communication System) >> Diagnostic Information and Procedures >> OnStar Reprogramming >> Vehicle Communication Unit (VCU)
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Vehicle Communication Unit (VCU)

WARNING: This page is about a different car, the 2002 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Record the ESN number from the label on the new part, (11 digits, no letters).
  2. Install the new VCU.
  3. After replacement, press and hold the OnStar "End Call" button (black with white dot); watch for the OnStar® status light change from Green to Red to Green.
  4. Press the blue OnStar® button to connect to OnStar®. Tell the advisor that this vehicle has a new VCU and a new ESN to put in the customers account. Follow any additional instructions given by the Advisor.
  5. The old VCU must be returned for core credit. Use the address label included in the original box. Failure to return core will result in a debit.
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