OBD Guide

P21F1

Cylinder 11 Injector B Circuit High

P21F1 is an OBD-II diagnostic trouble code meaning: Cylinder 11 Injector B Circuit High. Common causes: cylinder 11 injector malfunction, open or short circuit in the injector wiring harness. Estimated repair cost: $17–94.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–94 (est.)

Symptoms

  • Unstable engine operation
  • Increased fuel consumption
  • Misfire in cylinder 11
  • Check Engine Light Illuminates
  • Reduced engine power

Causes

  • Cylinder 11 injector malfunction
  • Open or short circuit in the injector wiring harness
  • Poor contact in the injector connector
  • Problems with the engine control module (ECU)
  • Short circuit to ground in control circuit

How to Fix

  1. Check the resistance of the injector of cylinder 11
  2. Inspect the wiring harness and connectors for damage
  3. Check injector control circuit for short circuit
  4. If necessary, replace the injector
  5. Test the operation of the system after repair

Related codes

Error P21F1 by Vehicle Brand

FAQ

What does the P21F1 code mean?

P21F1 is an OBD-II diagnostic trouble code that indicates: Cylinder 11 Injector B Circuit High

What causes a P21F1 error code?

The most common causes of P21F1 include: Cylinder 11 injector malfunction; Open or short circuit in the injector wiring harness; Poor contact in the injector connector; Problems with the engine control module (ECU).

How do I fix a P21F1 diagnostic trouble code?

To fix P21F1: Check the resistance of the injector of cylinder 11. Inspect the wiring harness and connectors for damage. Check injector control circuit for short circuit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21F1?

Limited driving only, diagnose soon

How much does it cost to fix P21F1?

The estimated repair cost for P21F1 is $17–94. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat