OBD Guide

P12F4

Cylinder Deactivation Exhaust Flow Valve Feedback Circuit Low Duty Cycle Bank 2

P12F4 is an OBD-II diagnostic trouble code meaning: Cylinder Deactivation Exhaust Flow Valve Feedback Circuit Low Duty Cycle Bank 2. Common causes: exhaust gas flow control valve malfunction, open or short circuit in control circuit. Estimated repair cost: $17–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Increased fuel consumption
  • Deterioration in acceleration dynamics
  • Unstable engine operation
  • Check Engine Light Is On
  • Cylinder deactivation system does not work

Causes

  • Exhaust gas flow control valve malfunction
  • Open or short circuit in control circuit
  • Problems with power or circuit ground
  • Engine control module malfunction
  • Mechanical damage or valve jamming

How to Fix

  1. Check valve control circuit integrity
  2. Check valve resistance and operation
  3. Clean or replace valve if necessary
  4. Check connections and connectors in the circuit
  5. If necessary, replace the engine control module

Related codes

FAQ

What does the P12F4 code mean?

P12F4 is an OBD-II diagnostic trouble code that indicates: Cylinder Deactivation Exhaust Flow Valve Feedback Circuit Low Duty Cycle Bank 2

What causes a P12F4 error code?

The most common causes of P12F4 include: Exhaust gas flow control valve malfunction; Open or short circuit in control circuit; Problems with power or circuit ground; Engine control module malfunction.

How do I fix a P12F4 diagnostic trouble code?

To fix P12F4: Check valve control circuit integrity. Check valve resistance and operation. Clean or replace valve if necessary. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P12F4?

Yes, but get it checked soon

How much does it cost to fix P12F4?

The estimated repair cost for P12F4 is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat