Why are my Brake, ABS, and/or Traction Control Lights on?
These symptoms will appear on the 2013+ 6.7L Cummins when the tire size is set with the engine running.
To correct the issue follow the steps below.
-Turn key on, but leave the engine off.
-Access the main menu on your GT device.
-Scroll down to "Diagnostics" and select clear DTC's.
-After you are back to the Main Menu, select the special functions option and navigate to "Tire size"
-Set your tire size to the correct size and follow the prompts
-Once complete, press "Go Back" until you see the main menu
-Turn key off, at this point the tire size has been properly set and the issue will be resolved.
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