Vehicle Interface Unit: Removal

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Removal
WARNING: This page is about a different car, the 2002 Chevrolet Monte Carlo, 2002 Chevrolet Impala, 2001 Chevrolet Monte Carlo, and 2001 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
  1. Open rear compartment. Remove cover from OnStar® Vehicle Communication Unit (VCU) by depressing retainer tabs. Remove cellular coaxial cable from VCU by pulling off. Remove screws from connector. Remove connector from VCU. Release retainer strap from VCU using a small flat-bladed tool. Remove VCU from rear compartment.
  2. Remove nuts from VIU/VCU bracket. Remove VIU from inner wheel housing. Disconnect Global Positioning System (GPS) antenna cable from VIU.
  3. Disconnect red 32-pin connector from VIU. Disconnect blue 32-pin connector from VIU. Remove mounting screws from VIU. Remove VIU from VIU/VCU bracket.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.