OBD Guide

P26AF

Engine Coolant Bypass Valve B Stuck/Open

P26AF is an OBD-II diagnostic trouble code meaning: Engine Coolant Bypass Valve B Stuck/Open. Common causes: mechanical valve sticking, valve contamination. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Unstable engine temperature
  • The engine is overheating
  • Long engine warm-up
  • Increased fuel consumption
  • Loss of engine power

Causes

  • Mechanical valve sticking
  • Valve contamination
  • Solenoid valve malfunction
  • Wiring problems
  • Engine control unit malfunction

How to Fix

  1. Check valve operation manually
  2. Clean or replace valve
  3. Check solenoid valve and wiring
  4. Check fuses and relays
  5. Diagnose the engine control unit

Related codes

Error P26AF by Vehicle Brand

FAQ

What does the P26AF code mean?

P26AF is an OBD-II diagnostic trouble code that indicates: Engine Coolant Bypass Valve B Stuck/Open

What causes a P26AF error code?

The most common causes of P26AF include: Mechanical valve sticking; Valve contamination; Solenoid valve malfunction; Wiring problems.

How do I fix a P26AF diagnostic trouble code?

To fix P26AF: Check valve operation manually. Clean or replace valve. Check solenoid valve and wiring. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P26AF?

Limited driving only, diagnose soon

How much does it cost to fix P26AF?

The estimated repair cost for P26AF is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat