C0004 critical

ABS Control Module Ground Circuit

The C0004 code means the vehicle's onboard diagnostic system has detected: ABS Control Module Ground Circuit. This is a critical severity code.

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Keep driving?
Short distances only
DIY difficulty
hard
Estimated cost
$50 - $300 (parts and labor)
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Common Symptoms

  • ABS warning light on
  • Multiple ABS codes stored
  • Intermittent ABS operation
  • Traction control disabled

Probable Causes (Ranked by Likelihood)

  • Corroded ABS module ground terminal Very High
  • Loose ground wire bolt High
  • Damaged ground wire insulation Moderate
  • Rusted body ground point Low

Step-by-Step Diagnostic Procedure

  1. Locate the ABS module ground point on the vehicle body

  2. Inspect ground wire and terminal for corrosion

  3. Measure voltage drop on the ground circuit

  4. Clean and secure all ABS module ground connections

Frequently Asked Questions

What causes a bad ABS module ground?

Corrosion is the most common cause, especially in areas with road salt. Loose bolts and damaged wires also contribute.

How do I test an ABS module ground?

Perform a voltage drop test on the ground circuit. With ABS active, voltage drop should be less than 0.1 volts.

Is fixing a ground connection expensive?

Ground circuit repairs are usually inexpensive, typically $50 to $300 including diagnostic time.

Sources

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

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