Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

OnStar - Vehicle Interface Unit (VIU)

1. Record the STID number from the label on the new module (10 Digits).
2. After replacement, press the blue OnStar button twice to connect to OnStar. Tell the advisor that this vehicle has a new VIU and a new STID number to put in the customers account.
3. The OnStar Advisor will reconfigure the vehicle with you. Once the advisor completes configuration, you can end the call. Follow any additional instructions given by the Advisor.
4. The old VIU must be returned for core credit with the address label included in the original box. Failure to return core will result in a debit.