P2055 serious

Reductant Injector Circuit Open (Bank 2 Unit 1)

The P2055 code means the vehicle's onboard diagnostic system has detected: Reductant Injector Circuit Open (Bank 2 Unit 1). This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
hard
Estimated cost
$300 - $900 (parts and labor)
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Common Symptoms

  • Check Engine Light on
  • DEF system fault warning
  • No DEF injection on Bank 2
  • Increased NOx emissions
  • Speed limiter may engage

Probable Causes (Ranked by Likelihood)

  • Open circuit in Bank 2 Unit 1 DEF injector wiring Very High
  • Failed Bank 2 DEF injector High
  • Corroded injector connector Moderate
  • Blown fuse for Bank 2 injector circuit Moderate
  • PCM output driver failure Low

Step-by-Step Diagnostic Procedure

  1. Confirm P2055 with freeze frame data

  2. Check fuse and relay for Bank 2 DEF injector

  3. Inspect injector connector and wiring for open circuits

  4. Measure injector coil resistance and compare to specification

Frequently Asked Questions

What does P2055 mean?

P2055 indicates an open circuit in the Bank 2 Unit 1 DEF injector, meaning no diesel exhaust fluid is being injected on that bank for NOx reduction.

Can I drive with a P2055 code?

Drive only short distances. Bank 2 NOx reduction is not functioning, and a speed limiter may be imposed.

How much does it cost to fix P2055?

Repairs typically cost $300 to $900 for DEF injector replacement or wiring repair.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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