OBD-II Code · Fuel & Air
P0201
Injector Circuit Malfunction — Cylinder 1
Severity
high
Left alone, this one tends to take other parts with it.
Can you drive it
Not for long
Driving on this one risks further damage. Get it to a shop rather than carrying on with it.
Indicative cost (USD)
$100–$500
Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
Cylinder 1 injector circuit fault.
How a shop works this
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed.
Note every code that is set, not just this one.
Codes that appear together usually narrow the cause faster than any one of them read alone.
Read the freeze frame — the conditions the fault was recorded under.
Cold or warm, idle or load, road speed and engine speed. A fault that only appears cold is a different fault from one that only appears under load, even with the same code on the scanner.
Confirm the fault is current rather than history.
Clear the code and see whether it returns under those same conditions. A code that does not come back may have been logged during a repair, a flat battery, or a bad connection that has since been disturbed.
Then work the likely-causes list in the order shown.
That order is what a shop checks first for this code — wiring and connections before the component they run to, because a connector costs nothing to inspect and is a common answer.
If the code comes back after a repair, the underlying fault is still there. That is the point to bring in a scanner with live data and freeze-frame, or a shop that has one.
Common symptoms
- Cyl 1 misfire
- Check engine light
- Rough idle
Likely causes
- Failed injector 1Most common
- Wiring to injector 1
- PCM driver fault
Read the full diagnostic procedureP0201 isolates the fault to the cylinder 1 injector driver circuit specifically, meaning the PCM commanded that injector on and either saw no current…
P0201 isolates the fault to the cylinder 1 injector driver circuit specifically, meaning the PCM commanded that injector on and either saw no current flow (open circuit), excessive current (shorted coil), or a driver-side fault on that one pin, while the other cylinders report normal.
Cheapest-first ladder
- swap the cylinder 1 injector with cylinder 3 or 4 and clear codes, drive the car, and see if the code follows the injector (confirms injector failure) or stays on cylinder 1 (confirms wiring or PCM driver); measure resistance at the cylinder 1 injector itself, which for port-fuel applications should be 11 to 17 ohms and within 0.5 ohm of the other cylinders, and for GDI direct-injection applications should be 1 to 3 ohms; check the connector for green corrosion or backed-out terminals and verify the 12V feed at the injector connector reads battery voltage key-on.
- A scan tool injector balance test should show cylinder 1 pulse-width matching the others within 0.2 ms at idle (typically 2.5 to 3.2 ms warm) before you condemn the injector.
- The expensive misdiagnosis is replacing the cylinder 1 injector ($180 to $450 on GDI engines after labor) when the real failure is a backed-out terminal in the connector or a broken pin inside the PCM that needs a $900 module rather than a $200 injector.
Vehicle-specific patterns2006-2013 BMW N54/N55 335i and 535i throw P0201 routinely after injector replacement when the new injector's six-digit index code is not coded into t…
- 2006-2013BMW N54/N55 335i and 535i throw P0201 routinely after injector replacement when the new injector's six-digit index code is not coded into the DME via ISTA (BMW SIB 13 01 13 mandates index coding to match flow rate, uncoded injectors cause balance faults on cylinder 1 first because it is closest to the rail inlet);
- 2011-2019Ford 3.5L EcoBoost F-150 throws P0201 from carbon-tip fouling on cylinder 1 because the front cylinder runs leanest under boost, and a walnut-shell intake-valve cleaning plus injector replacement is typical at 80k to 100k miles;
- 2008-2014VW/Audi 2.0T (EA888) trips P0201 when the high-pressure direct injector's solenoid coil opens, often after extended ethanol exposure;
- 2003-2008Honda Accord 2.4L K24 sees P0201 from a clogged port injector after years on ethanol-blend fuel, cleanable with a Motorvac service.
Estimated repair$80 to $850.
Look up another code
P0201 — frequently asked
What does a P0201 code mean?
Cylinder 1 injector circuit fault.
What causes a P0201 code?
Common causes: Failed injector 1; Wiring to injector 1; PCM driver fault.
What are the symptoms of a P0201 code?
Typical symptoms: Cyl 1 misfire; Check engine light; Rough idle.
Is it safe to drive with a P0201 code?
Not for long. Driving on this one risks further damage. Get it to a shop rather than carrying on with it. Estimated repair: $100-$500.
How do I diagnose a P0201 code?
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed. 1. Note every code that is set, not just this one. 2. Read the freeze frame — the conditions the fault was recorded under. 3. Confirm the fault is current rather than history. 4. Then work the likely-causes list in the order shown.
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