OBD Codes

U0190

Lost Communication with Trailer Control Module

Moderateelectrical

Overview

The U0190 diagnostic trouble code indicates lost communication with trailer control module. This means one or more control modules on the vehicle's communication network are unable to exchange data properly. Network communication faults can affect multiple vehicle systems simultaneously and may cause various warning lights, reduced functionality, or driveability issues depending on which modules are affected.

Symptoms

  • Transmission shifting erratically or stuck in one gear
  • HVAC system not responding
  • Vehicle may not start or stall unexpectedly
  • Instrument cluster displays blank or flickering

Common Causes

  • Aftermarket device interfering with CAN bus
  • Poor ground connection at module
  • Failed gateway module blocking communication
  • Water damage to module or wiring harness

Diagnosis Steps

  1. 1Connect an OBD-II scanner and read all stored trouble codes across all modules
  2. 2Check for multiple U-codes which indicate a bus-level problem vs single module failure
  3. 3Inspect battery voltage and charging system (12.4V+ engine off, 13.5-14.5V running)
  4. 4Inspect the CAN bus wiring for damage, chafing, or exposed conductors
  5. 5Check the affected module connector for corrosion, bent pins, or water intrusion
  6. 6Verify module power and ground circuits with a multimeter

Estimated Repair Cost

$100$1,500

Cost varies by vehicle, location, and repair shop. Includes parts and labor.

Commonly Affected Vehicles

Honda AccordKia OptimaChevrolet EquinoxChevrolet Silverado

Related Codes

More Electrical Codes

Frequently Asked Questions

U-codes are network communication codes that indicate a control module has lost communication with another module. This can be caused by wiring problems, a failed module, low battery voltage, or CAN bus issues. Multiple U-codes usually point to a bus-level problem.