U0499 moderate

Invalid Data Received From Vehicle Security Module

The U0499 code means the vehicle's onboard diagnostic system has detected: Invalid Data Received From Vehicle Security Module. This is a moderate severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
hard
Estimated cost
$200 - $900 (parts and labor)
Diagnose CAN Bus Issues
LAUNCH CRP123X Full System Scanner

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

  • Vehicle security warning persistent
  • Immobilizer activating randomly
  • Starter disabled intermittently
  • Multiple security warnings
  • Remote start not working

Probable Causes (Ranked by Likelihood)

  • Security module internal fault Very High
  • Key recognition system error High
  • CAN bus data corruption at security module Moderate
  • Aftermarket alarm interference Low

Step-by-Step Diagnostic Procedure

  1. Remove aftermarket alarm if installed

  2. Try all available keys

  3. Scan security module for codes

  4. Check CAN bus at security module

Frequently Asked Questions

Can I drive with U0499?

Yes, but the vehicle may randomly not start. Keep a spare key available.

What causes U0499?

Often aftermarket alarm systems interfering with factory security.

How much to fix?

Between $200 and $900. Removing aftermarket alarms may resolve it.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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