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OnStar - VCU or VIU Reprogramming

VCU OR VIU REPROGRAMMING

IMPORTANT: The new OnStar component parts must be installed prior to the reconfiguration of the OnStar system.

After replacement of the vehicle communication unit (VCU) or vehicle interface unit (VIU), the OnStar system must be reprogrammed.
1. Press and hold the Answer/End Button on the OnStar Button Assembly until the System Status Light goes from solid GREEN to RED and back to GREEN again.
2. Call the OnStar Call Center at 1-888-OnStar1, select prompt 1.
3. Give the operator the Electronic Serial Number (ESN) off the new VCU or the Station ID (STID) number off the VIU.
4. Move the vehicle outside and let the vehicle in for 10 minutes.
5. Press the OnStar Call Center Call button and ask for a "Reconfiguration".