OBD Guide

U02B9

Lost Communication With Rear Radar Module D

U02B9 is an OBD-II diagnostic trouble code meaning: Lost Communication With Rear Radar Module D. Common causes: broken or damaged wires to the rear radar, rear radar module malfunction. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–278 (est.)

Symptoms

  • Rear parking sensors do not work
  • Disabling the Blind Spot Warning System
  • Error message on the dashboard
  • The Check Engine or other systems light comes on
  • Inability to activate parking assist features

Causes

  • Broken or damaged wires to the rear radar
  • Rear radar module malfunction
  • Connector problems or contact corrosion
  • Failures in ECU software
  • Radar module power supply problems

How to Fix

  1. Check the integrity of the wiring to the rear radar
  2. Inspect connectors for corrosion or damage
  3. Check the power and ground of the radar module
  4. Scan the radar module for errors
  5. If necessary, replace the rear radar module
  6. Repair only from an authorized dealer

Related codes

Error U02B9 by Vehicle Brand

FAQ

What does the U02B9 code mean?

U02B9 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Rear Radar Module D

What causes a U02B9 error code?

The most common causes of U02B9 include: Broken or damaged wires to the rear radar; Rear radar module malfunction; Connector problems or contact corrosion; Failures in ECU software.

How do I fix a U02B9 diagnostic trouble code?

To fix U02B9: Check the integrity of the wiring to the rear radar. Inspect connectors for corrosion or damage. Check the power and ground of the radar module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U02B9?

Do not drive — repair immediately

How much does it cost to fix U02B9?

The estimated repair cost for U02B9 is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat