Injector Circuit Malfunction - Cylinder 1
The P0201 code means the vehicle's onboard diagnostic system has detected: Injector Circuit Malfunction - Cylinder 1. This is a serious severity code.
- Keep driving?
- Limited driving only
- DIY difficulty
- medium
- Estimated cost
- $25-$50 for wiring repair; $100-$400 for injector
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What Are the Symptoms of P0201?
- Check Engine Light on
- Misfire on cylinder 1
- Rough idle
- Power loss
- Fuel smell from exhaust
What Causes P0201? (Most Likely First)
- Open or short in cylinder 1 injector circuit Very High
- Failed cylinder 1 fuel injector High
- Damaged wiring or connector at cylinder 1 injector High
- PCM driver fault for cylinder 1 injector Moderate
Can I Still Drive with P0201?
Limited driving only. P0201 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Common Fixes by Vehicle
What techs usually find when diagnosing P0201 on specific vehicles — tap your vehicle for the fix and the exact part:
2009-2020 Ford F-150/Explorer 3.5L EcoBoost Moderate DIY
Cylinder 1 fuel injector circuit malfunction. Check the injector connector for backed-out pins or corrosion. Measure injector resistance -- should be 11-15 ohms. If open or shorted, replace the injector. On EcoBoost engines, carbon buildup on direct injector tips causes sticking. Your dealer can confirm whether an open service bulletin or warranty extension applies to your VIN.
Labor: 1-2 hours2007-2017 Toyota Camry 2.5L Moderate DIY
Injector 1 circuit open or shorted. Check the injector connector first for corrosion or damage. Measure injector coil resistance -- should be 11-16 ohms. If the resistance is correct, check the wiring from the ECU to the injector for an open or short circuit. Replace the injector with Denso if coil resistance is out of spec. Confirm the exact part for your year and engine with a retailer's fitment lookup or your VIN before ordering - these applications split by engine and build date.
Labor: 1-1.5 hours2010-2020 Chevrolet Silverado/GMC Sierra 5.3L Moderate DIY
Cylinder 1 injector circuit fault. Check the injector connector and measure resistance (should be 11-13 ohms). If the connector has oil contamination from a valve cover leak, clean and reseal. If resistance is out of spec, replace with an OE-quality ACDelco unit. Swap the injector with another cylinder to confirm the fault follows the injector. Confirm the exact part for your year and engine with a retailer's fitment lookup or your VIN before ordering - these applications split by engine and build date.
Labor: 1-2 hoursFrequently Asked Questions
Should I replace all injectors if one fails?
Not necessarily. If the injector failed due to contamination or electrical damage, replacing only the failed unit is fine. If the engine has very high mileage and poor maintenance history, a set replacement may be more cost-effective.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0201?
-
Identify cylinder 1 location on your engine.
-
Plug a NOID light into the cylinder 1 injector connector. Crank the engine and observe flashing.
-
If NOID flashes, the PCM driver is OK. Test the injector resistance (should be 11-17 ohms high-impedance).
-
No NOID flash: check wiring from injector to PCM for breaks or shorts.
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Replace injector if resistance is out of spec or if it leaks fuel with no electrical pulse.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
P0201 on Diesel, EV & Equipment
The same code ID appears across other engines and platforms. The diagnostic flow varies by manufacturer — these are the platform-specific breakdowns:
Which Vehicles Commonly Get P0201?
- Ford F-150 (4.6L, 5.4L)
- Chevrolet Silverado
- Dodge Ram (5.7L HEMI)
- Toyota Camry
- Honda Accord
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