Refusing a preliminary breath test (PBT) will result in:

Michigan has an Implied Consent Law, which means that by operating a vehicle in the state, you are understood to have consented to a chemical test if authorities ask you for one. If you refuse to submit to a test, your CDL will be suspended for at least one year for a first-time offense. Refusing a preliminary breath test (PBT) will also result in being placed out-of-service for 24 hours.