ECM/PCM Power Input Signal Intermittent
The DURAMAX-P2509 (Duramax) diesel fault code means: ECM/PCM Power Input Signal Intermittent. This is a moderate severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P2509?
- Check Engine Light on
- Possible stalling, no start or intermittent electrical faults
What Causes DURAMAX-P2509? (Most Likely First)
- Weak batteries or poor charging High
- Loose or corroded battery, ground or fuse connections High
- Damaged power feed wiring to the engine computer Moderate
Can I Still Drive with DURAMAX-P2509?
Yes, with caution. DURAMAX-P2509 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P2509 mean on a Duramax?
P2509 means ECM/PCM Power Input Signal Intermittent. The engine computer is seeing its power input signal drop out intermittently.
Is P2509 a Duramax-specific code?
No. P2509 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-P2509?
Test the batteries and charging voltage.
Clean and tighten battery and ground connections and check the engine computer fuses.
Wiggle-test the power feed and watch the voltage reading on a scan tool.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P2509 as a generic OBD-II code)
P2509 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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