Invalid Data Received From Heated Mirror Module
The U0494 code means the vehicle's onboard diagnostic system has detected: Invalid Data Received From Heated Mirror Module. This is a low severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- easy
- Estimated cost
- $100 - $300 (parts and labor)
Network codes mean modules are not communicating. You need a scanner that reads all systems to find the problem.
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Common Symptoms
- Mirror heaters not clearing fog or ice
- One mirror heating but not the other
- Mirror heater staying on too long
- Mirror heater indicator not working
Probable Causes (Ranked by Likelihood)
- Mirror heating element failure Very High
- Mirror module data error High
- CAN bus fault Moderate
- Mirror wiring fault Low
Step-by-Step Diagnostic Procedure
-
Test mirror heater element resistance
-
Check mirror wiring
-
Scan mirror heater module
-
Verify power supply to mirrors
Frequently Asked Questions
Can I drive with U0494?
Yes. Scrape mirrors manually in cold weather.
What causes U0494?
Usually a failed heating element in the mirror glass.
How much to fix?
Typically $100 to $300.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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