OnStar Advanced Diagnostics can help you find out exactly what auto maintenance or repair needs to be done on your vehicle.

OnStar® Vehicle Diagnostics1 is the easiest and most comprehensive way to get your vehicle’s information sent to you. It lets you know the status of key systems with a monthly diagnostics report or diagnostic alerts — available in real-time by email or text and also through your MyChevrolet, MyGMC, MyBuick, or MyCadillac owner’s app. Running a check on your engine, transmission, antilock brakes and other key systems helps you to know your car is properly maintained and in top condition. Your vehicle can even notify your preferred dealer when it’s time for maintenance. They’ll contact you to set up an appointment. With OnStar Vehicle Diagnostics, you know more and worry less.


For enrolled subscribers, OnStar Vehicle Diagnostics1 is a powerfully simple way to determine what’s going on under the hood. It offers peace of mind by checking in with you every month or in real-time to help make sure your vehicle is ready for the road. There are two major features:

1. Diagnostic Alerts

  • Every month OnStar Vehicle Diagnostics1 can automatically send you an easy to read diagnostic report via email with the results of hundreds of checks of your engine, transmission, anti-lock brakes, and other key operating systems.
  • If you prefer, you can also be notified of your vehicle’s condition in real time by email or text or through your owner’s app.
  • It's a consistent reminder of what's going on — specific to your vehicle — and what steps are involved in maintaining it.
  • Simple colour-coded icons make the report easy to review in seconds. A green icon next to a system means no issues were found. A yellow icon tells you action is suggested. And a red icon means you need to take action immediately.
  • It tells you when you're due for scheduled maintenance.
  • It also gives you the status of your OnStar subscription and profile, Hands-Free Calling minutes, and Turn-by-Turn Navigation.

2. Dealer Maintenance Notification1

Time for a tire rotation? A tune-up? A new air filter? You’ll always know because your car can notify your preferred dealer when it’s time, and they’ll contact you to set up an appointment should maintenance be needed. Your car is self-diagnosing so you can enjoy the experience of driving.

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