Injector Circuit/Open - Cylinder 4
The DURAMAX-P0204 (Duramax) diesel fault code means: Injector Circuit/Open - Cylinder 4. This is a serious severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0204?
- Check Engine Light on
- Rough running or misfire
- Smoke from the exhaust
- Reduced power
What Causes DURAMAX-P0204? (Most Likely First)
- Open or damaged wiring to the cylinder 4 injector High
- Failed injector coil High
- Corroded or loose injector connector Moderate
- Injector driver fault in the control module Low
Can I Still Drive with DURAMAX-P0204?
Yes, with caution. DURAMAX-P0204 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0204 mean on a Duramax?
P0204 means Injector Circuit/Open - Cylinder 4. The engine computer has detected an open or faulty electrical circuit for the cylinder 4 injector.
Is P0204 a Duramax-specific code?
No. P0204 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-P0204?
Check the cylinder 4 injector harness and connector for damage and corrosion.
Measure the injector coil resistance and compare it with the specification.
Check the circuit for continuity back to the control module.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0204 as a generic OBD-II code)
P0204 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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