OBD Guide

U0425

Invalid Data Received From Auxiliary Heater Control Module

U0425 is an OBD-II diagnostic trouble code meaning: Invalid Data Received From Auxiliary Heater Control Module. Common causes: malfunction of the additional heater control module, damage to the wiring harness to the heater. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Auxiliary heater does not work
  • Error message on the dashboard
  • Reduced interior heating efficiency
  • Problems starting the engine in cold weather (for diesel engines)

Causes

  • Malfunction of the additional heater control module
  • Damage to the wiring harness to the heater
  • Poor contact in connectors
  • Software error in the ECU
  • Heater module power supply problems

How to Fix

  1. Check the integrity of the wiring harness to the heater
  2. Check connections and contacts in connectors
  3. Test the heater control module
  4. Update ECU software
  5. Replace the control module if necessary

Related codes

Error U0425 by Vehicle Brand

FAQ

What does the U0425 code mean?

U0425 is an OBD-II diagnostic trouble code that indicates: Invalid Data Received From Auxiliary Heater Control Module

What causes a U0425 error code?

The most common causes of U0425 include: Malfunction of the additional heater control module; Damage to the wiring harness to the heater; Poor contact in connectors; Software error in the ECU.

How do I fix a U0425 diagnostic trouble code?

To fix U0425: Check the integrity of the wiring harness to the heater. Check connections and contacts in connectors. Test the heater control module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0425?

Yes, but get it checked soon

How much does it cost to fix U0425?

The estimated repair cost for U0425 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat