DTC U0121-87: Lost Communication With Anti-Lock Brake System (ABS) Control Module - Missing message: Action
- Using the manufacturer approved diagnostic system check anti-lock brake system control module for related DTCs and refer to the relevant DTC index
- Using the manufacturer approved diagnostic system complete a CAN network integrity test
- Refer to the appropriate system wiring diagrams and check the power and ground connections to the anti-lock brake system control module
- Check CAN harness between engine control module and antilock brake system control module. Repair as necessary