U0133
System
Network (CAN Bus)
Scanner required
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Lost Communication with Active Roll Control Module

Understand U0133, common causes, and the right SEAFLO pump to diagnose it.

Active anti-roll or suspension control module offline on luxury SUVs and performance vehicles.

Common symptoms

  • Suspension warning
  • Handling feels different
  • Multiple chassis U-codes

Typical causes

  • Failed ARC module
  • CAN wiring to suspension
  • Low voltage
  • Aftermarket suspension wiring conflict

What scanner do you need?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Use live data and freeze frame to confirm the fault before replacing parts. ABS, SRS, and network U-codes usually require a full-system scanner.

Diagnostic tips

  • Record freeze frame data when the code first sets
  • Clear the code only after fixing the root cause
  • Check for related pending codes that point to a common issue
  • Verify battery voltage is above 12.4V before chasing sensor codes

Frequently asked questions

Can I diagnose U0133 with a basic code reader?
U0133 may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Is it safe to drive with U0133?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.