Injector Circuit/Open - Cylinder 3
The POWERSTROKE-P0203 (Power Stroke) diesel fault code means: Injector Circuit/Open - Cylinder 3. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- advanced
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What Are the Symptoms of POWERSTROKE-P0203?
- Check Engine Light on
- Rough running or misfire
- Smoke from the exhaust
- Reduced power
What Causes POWERSTROKE-P0203? (Most Likely First)
- Open or damaged wiring to the cylinder 3 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 POWERSTROKE-P0203?
Short distances only. POWERSTROKE-P0203 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0203 mean on a Power Stroke?
P0203 means Injector Circuit/Open - Cylinder 3. The engine computer has detected an open or faulty electrical circuit for the cylinder 3 injector.
Is P0203 a Power Stroke-specific code?
No. P0203 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 Ford uses to set it on its diesels are in Ford service information.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose POWERSTROKE-P0203?
Check the cylinder 3 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 P0203 as a generic OBD-II code)
P0203 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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