OBD Guide

P2CF1

Auxiliary Thermostat B Stuck Open

P2CF1 is an OBD-II diagnostic trouble code meaning: Auxiliary Thermostat B Stuck Open. Common causes: mechanical wear of the thermostat, thermostat valve stuck. Estimated repair cost: $17–67.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–67 (est.)

Symptoms

  • Long engine warm-up
  • Increased fuel consumption
  • Reduced engine temperature at idle
  • Insufficient interior heating in winter
  • Check Engine Light Is On

Causes

  • Mechanical wear of the thermostat
  • Thermostat valve stuck
  • Debris getting into the thermostat mechanism
  • Electrical problems (for electronic thermostats)
  • Corrosion of thermostat components

How to Fix

  1. Cooling system diagnostics
  2. Checking the functionality of thermostat B
  3. Replacing a faulty thermostat
  4. Flushing the cooling system
  5. Reset error and test drive

Related codes

Error P2CF1 by Vehicle Brand

FAQ

What does the P2CF1 code mean?

P2CF1 is an OBD-II diagnostic trouble code that indicates: Auxiliary Thermostat B Stuck Open

What causes a P2CF1 error code?

The most common causes of P2CF1 include: Mechanical wear of the thermostat; Thermostat valve stuck; Debris getting into the thermostat mechanism; Electrical problems (for electronic thermostats).

How do I fix a P2CF1 diagnostic trouble code?

To fix P2CF1: Cooling system diagnostics. Checking the functionality of thermostat B. Replacing a faulty thermostat. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P2CF1?

Yes, but get it checked soon

How much does it cost to fix P2CF1?

The estimated repair cost for P2CF1 is $17–67. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat