OBD Guide

C123B

ESP System Control Too Long

C123B is an OBD-II diagnostic trouble code meaning: ESP System Control Too Long. Common causes: malfunction of wheel speed sensors, problems with esp wiring harness. Estimated repair cost: $33–167.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$33–167 (est.)

Symptoms

  • ESP/ABS indicator is on
  • Unstable operation of the stabilization system
  • The car loses control when cornering

Causes

  • Malfunction of wheel speed sensors
  • Problems with ESP wiring harness
  • ESP control unit malfunction
  • Corroded or damaged connectors

How to Fix

  1. Diagnose the ESP and ABS system using a scanner
  2. Check wheel speed sensors and their connectors
  3. Inspect the wiring harness for damage
  4. If necessary, replace faulty components or the entire control unit

Related codes

FAQ

What does the C123B code mean?

C123B is an OBD-II diagnostic trouble code that indicates: ESP System Control Too Long

What causes a C123B error code?

The most common causes of C123B include: Malfunction of wheel speed sensors; Problems with ESP wiring harness; ESP control unit malfunction; Corroded or damaged connectors.

How do I fix a C123B diagnostic trouble code?

To fix C123B: Diagnose the ESP and ABS system using a scanner. Check wheel speed sensors and their connectors. Inspect the wiring harness for damage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C123B?

Do not drive — repair immediately

How much does it cost to fix C123B?

The estimated repair cost for C123B is $33–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat