U0155
System
Network (CAN Bus)
Scanner required
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Lost Communication with Instrument Panel Cluster

Understand U0155, common causes, and the right TOPDON scanner to diagnose it.

The ECM or another module cannot communicate with the instrument cluster. Often appears with other U-codes after battery disconnect or low voltage.

Common symptoms

  • Gauge or display anomalies
  • Multiple warning lights
  • Intermittent no-start

Typical causes

  • Low system voltage
  • Faulty instrument cluster
  • CAN wiring issue
  • Corrosion in connector at cluster

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

Recommended TOPDON scanners

Frequently asked questions

Can I diagnose U0155 with a basic code reader?
U0155 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 U0155?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.