DURAMAX-P0605 critical Duramax ›

Internal Control Module Read Only Memory (ROM) Error

The DURAMAX-P0605 (Duramax) diesel fault code means: Internal Control Module Read Only Memory (ROM) Error. This is a critical severity code.

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Keep driving?
No — stop driving
DIY difficulty
intermediate
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What Are the Symptoms of DURAMAX-P0605?

  • Check Engine Light on
  • Possible no start or stalling
  • Possible erratic running or loss of stored settings

What Causes DURAMAX-P0605? (Most Likely First)

  • Internal control module fault High
  • Poor power or ground supply to the module Moderate
  • Corrupted software, often after an interrupted programming event Moderate

Can I Still Drive with DURAMAX-P0605?

No — stop driving. DURAMAX-P0605 is rated critical severity. Continuing to drive in this state risks further damage — get it looked at before your next trip.

Frequently Asked Questions

What does P0605 mean on a Duramax?

P0605 means Internal Control Module Read Only Memory (ROM) Error. The control module has found a fault in its own read only memory during a self-test.

Is P0605 a Duramax-specific code?

No. P0605 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions GM uses to set it on its diesels are in GM service information.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose DURAMAX-P0605?

  1. Check battery voltage and the module power and ground circuits first.

  2. Check whether a software update is available for the module.

  3. Reprogram the module before replacing it, and replace it only if the code returns.

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0605 as a generic OBD-II code)

P0605 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

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