P2059 serious

Reductant Injector Circuit Open (Bank 2 Unit 2)

The P2059 code means the vehicle's onboard diagnostic system has detected: Reductant Injector Circuit Open (Bank 2 Unit 2). This is a serious severity code.

My Garage →
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 malfunction indicator
  • No DEF injection from Bank 2 Unit 2
  • Elevated tailpipe NOx emissions
  • Speed limiter may be activated

Probable Causes (Ranked by Likelihood)

  • Open circuit in Bank 2 Unit 2 DEF injector wiring Very High
  • Failed Bank 2 Unit 2 DEF injector High
  • Disconnected or damaged connector Moderate
  • Blown fuse or relay Moderate
  • PCM output driver failure Low

Step-by-Step Diagnostic Procedure

  1. Read freeze frame data and confirm P2059

  2. Check fuse and relay for Bank 2 DEF injector Unit 2

  3. Inspect wiring and connector to Unit 2 injector for open circuits

  4. Measure injector coil resistance and compare to OEM specification

Frequently Asked Questions

What does P2059 mean?

P2059 indicates an open circuit in the Bank 2 Unit 2 DEF injector, preventing diesel exhaust fluid from being injected at that location for NOx reduction.

Can I drive with a P2059 code?

Drive only short distances. Without proper DEF injection, NOx emissions are uncontrolled and driving restrictions may apply.

How much does it cost to fix P2059?

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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