OBD Guide

C066E

Service/Park Brake Chamber Pressure Too High

C066E is an OBD-II diagnostic trouble code meaning: Service/Park Brake Chamber Pressure Too High. Common causes: pressure reducer malfunction, brake valve stuck. Estimated repair cost: $111–333.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$111–333 (est.)

Symptoms

  • The brake system fault indicator is on
  • The parking brake may engage spontaneously
  • Difficulty releasing the parking brake

Causes

  • Pressure reducer malfunction
  • Brake valve stuck
  • Leak in the pneumatic system
  • Pressure sensor malfunction
  • Wiring harness damage

How to Fix

  1. Check system pressure
  2. Inspect air lines for leaks
  3. Check the operation of the brake valve
  4. Check the pressure sensor and its circuits
  5. Replace faulty components

Related codes

Error C066E by Vehicle Brand

FAQ

What does the C066E code mean?

C066E is an OBD-II diagnostic trouble code that indicates: Service/Park Brake Chamber Pressure Too High

What causes a C066E error code?

The most common causes of C066E include: Pressure reducer malfunction; Brake valve stuck; Leak in the pneumatic system; Pressure sensor malfunction.

How do I fix a C066E diagnostic trouble code?

To fix C066E: Check system pressure. Inspect air lines for leaks. Check the operation of the brake valve. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C066E?

Do not drive — repair immediately

How much does it cost to fix C066E?

The estimated repair cost for C066E is $111–333. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat