P0202: Injector Circuit/Open, Cylinder 2 (Meaning, Causes, Fixes)
What P0202 means
The powertrain control module (PCM) turns each fuel injector on and off using transistors that RepairPal calls drivers. OBD-Codes.com explains that when the injector is switched on the PCM expects the voltage on its control wire to be pulled low, close to zero, and when it is switched off it expects close to battery voltage. If the PCM doesn't see the expected voltage, or the circuit resistance is excessively high or low, it sets P0202. RepairPal says the code sets when the PCM sees an open or short in the cylinder 2 injector circuit. The two sources name it slightly differently: OBD-Codes.com calls it Cylinder 2 Injector Circuit Malfunction and RepairPal calls it Injector Circuit/Open, Cylinder 2, but they describe the same fault. It is a generic OBD-II code, though repair steps vary by make and model. P0201 and P0203 through P0212 cover the other cylinders, and P0200 is the general injector circuit code.
Severity: can I keep driving?
Stop and fix promptly
Get it diagnosed soon and don't ignore it. RepairPal rates P0202 Urgent, meaning it can cause severe damage or be unsafe. OBD-Codes.com says it will likely cause a misfire, rough running and poor acceleration. If the check engine light is flashing, the engine is shaking badly, or it loses power, keep driving to a minimum and have it checked, since a misfiring cylinder can damage other parts.
Common symptoms
- Check engine light on (both sources)
- Misfire and rough running (both sources; RepairPal says the vehicle may run rough)
- Poor acceleration (OBD-Codes.com)
- Poor fuel economy (RepairPal)
- Failed emissions inspection, either because the check engine light is on or because emissions are elevated (RepairPal)
- In rare cases, nothing the driver notices (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Bad cylinder 2 fuel injector (both sources; OBD-Codes.com says this is usually the cause)
- Open or shorted wiring to the injector (OBD-Codes.com), or defective wiring and connections in the injector harness (RepairPal)
- Defective injector power circuit (RepairPal)
- Fault in the PCM's injector driver circuit (RepairPal), or a bad PCM (OBD-Codes.com)
- The sources lean differently: OBD-Codes.com points first to the injector, while RepairPal gives equal weight to the injector, the PCM driver, the harness and the injector power feed
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Read all stored codes and write down the freeze frame data, which shows when the fault happened (RepairPal). Misfire codes such as P0302 or P0300 often appear alongside P0202.
- Visually check the cylinder 2 injector, its connector and wiring for damage or broken wires (both sources).
- With a digital multimeter, check the injector's resistance against your vehicle's spec (both sources), and check for at least 10 volts at the injector connector (OBD-Codes.com; RepairPal checks for power while cranking).
- If you can't test the injector directly, OBD-Codes.com suggests swapping it with another cylinder's injector and seeing whether the code follows it, for example changing to P0201 or P0203. If it moves, the injector is bad.
- Don't replace spark plugs for this code without testing first; RepairPal lists that as a common misdiagnosis when the real problem is the injector or the wiring harness.
- Avoid grounding PCM wires unless you are certain you have the correct wire; OBD-Codes.com warns not to attempt it if you're unsure.
Typical fixes
- Repair damaged, open or shorted wiring or bad connections in the cylinder 2 injector circuit, including its power feed (both sources)
- Replace the cylinder 2 fuel injector if it is out of spec or the code follows it (both sources)
- Repair or replace the PCM only after the injector, harness and power feed test good (both sources list the PCM as a possible cause)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- The check engine light is flashing or the engine runs very rough
- Confirming the circuit needs a noid light, harness continuity tests with the PCM disconnected, or a lab scope on the PCM driver signal, which RepairPal describes for shops
- The injector and wiring test good and the code returns, which can point to the PCM
- Several injector codes appear at once, which suggests a shared power feed or wiring problem rather than one injector
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Is P0202 serious?
Treat it as serious. RepairPal rates it Urgent, and OBD-Codes.com says it will likely cause a misfire and rough running. Get it diagnosed soon.
Is P0202 always a bad injector?
No. OBD-Codes.com says the injector is usually the cause, but RepairPal also lists the injector wiring, the injector power circuit and the PCM's driver circuit. Test before buying parts.
Will new spark plugs fix P0202?
Usually not. RepairPal lists replacing spark plugs as a common misdiagnosis when the real cause is a bad injector or wiring harness.
How much does it cost to fix P0202?
Neither source gives a repair cost. The price depends on whether it's wiring, the injector, or the PCM, so get a diagnosis or a written estimate before replacing parts.
Sources
Last reviewed 2026-10-22. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.