U1021 Code – Lost Communication With Anti-Lock Brake System Control Module

What are the Possible Causes of the Code U1021?
  • Faulty Anti-Lock Brake System (ABS) Control Module
  • Anti-Lock Brake System Control Module harness is open or shorted
  • Anti-Lock Brake System Control Module circuit poor electrical connection
  • Faulty Powertrain Control Module (PCM)
  • Need help with this OBD II code? Our mechanics are available within west Michigan to help. Outside of our service area? Visit our Car Help Section where you can ask questions and get answers.

Leave a Reply