CAN network

U0230 — Lost Communication with Rear Gate Module

Severity: low Safe to drive

What U0230 means

U0230 is set when another control unit, usually the BCM or a gateway, stops receiving messages from the rear gate (liftgate or tailgate) module on the CAN or LIN network. This module normally exchanges data constantly and responds to the key fob, buttons and sensors. When it goes silent, the system logs a loss of communication.

Symptoms

  • Power liftgate or tailgate does not work
  • Gate will not open from the button, key fob or hands-free sensor
  • BCM warning messages in the instrument cluster
  • Several warning lamps may be on
  • Functions handled by the affected module are unavailable

Possible causes

  1. Failed rear gate module
  2. Damaged wiring in the tailgate harness
  3. Water intrusion into the module or connector
  4. CAN bus wiring fault (open, short or chafed harness)
  5. Another faulty module loading down the bus
  6. Corroded connector or terminals
  7. Power supply or ground fault at the module

How to diagnose

  1. Run a full-system scan and map which modules are not communicating
  2. Look for other U-codes that point to a wider network problem
  3. Measure CAN bus resistance and voltages at the diagnostic connector
  4. Inspect the harness in the boot or conduit between the body and the gate for breaks and chafing
  5. Check module connectors for moisture, corrosion and a loose fit
  6. Test the module's power feed, fuses and ground
  7. Disconnect suspect modules one at a time only following a documented procedure

Common fixes

  • Repair or replace the damaged section of wiring
  • Clean and dry connectors, replace corroded terminals
  • Restore the module's power and ground
  • Replace the rear gate module and code it if required
  • Repair the faulty module that is disrupting the bus

Questions and answers

What does code U0230 mean?

It means a loss of communication with the rear gate module that controls the power liftgate or tailgate. The control unit is no longer getting data from it, so related functions stop working.

Can I drive with a U0230 code?

Usually yes, because it does not affect how the car drives. The power gate may not open, so it's best to find the cause soon.

What most often causes U0230?

Most often it's damaged wiring near the tailgate, water or corrosion in a connector, or a power or ground problem at the module. Less often the module itself or a CAN bus fault is to blame.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.