OBD Guide

U02A5

Lost Communication With Reductant Heater Control Module

U02A5 is an OBD-II diagnostic trouble code meaning: Lost Communication With Reductant Heater Control Module. Common causes: open or short circuit in the heating module circuit, malfunction of the reagent heating control module. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine Light Is On
  • Reduced engine power
  • SCR system error message on dashboard
  • Increased emissions
  • Problems starting in cold weather

Causes

  • Open or short circuit in the heating module circuit
  • Malfunction of the reagent heating control module
  • Problems with the CAN bus
  • Faulty relay or fuse
  • Poor contact in connectors

How to Fix

  1. Check fuses and relays associated with the system
  2. Inspect the wiring harness and connectors for damage.
  3. Check the power supply and ground of the heating module
  4. Diagnose the CAN bus for communication errors
  5. If necessary, replace the heating control module

Related codes

Error U02A5 by Vehicle Brand

FAQ

What does the U02A5 code mean?

U02A5 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Reductant Heater Control Module

What causes a U02A5 error code?

The most common causes of U02A5 include: Open or short circuit in the heating module circuit; Malfunction of the reagent heating control module; Problems with the CAN bus; Faulty relay or fuse.

How do I fix a U02A5 diagnostic trouble code?

To fix U02A5: Check fuses and relays associated with the system. Inspect the wiring harness and connectors for damage.. Check the power supply and ground of the heating module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U02A5?

Limited driving only, diagnose soon

How much does it cost to fix U02A5?

The estimated repair cost for U02A5 is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat