Injector Circuit Range/Performance Problem (Cylinder 1)
There’s a problem with the injector circuit for cylinder 1.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer thinks the fuel injector for the first cylinder isn't working right, either not getting enough power or not responding correctly.
What the computer is actually seeing
The engine control module (ECM) monitors injector resistance and circuit performance based on voltage and current readings. A significant deviation from the expected values triggers this code.
What a healthy reading looks like
Expected voltage at the injector connector should be around 12V with the ignition on and 0V when solidly grounded during operation. Resistance should typically be between 12-16 ohms.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the vehicle's battery voltage; it should be between 12.4V - 12.8V.
- 2Inspect the wiring and connector at injector #1 for damage, corrosion, or loose connections. Repair as needed.
- 3Using a multimeter, check the resistance of the injector; it should be between 12-16 ohms. If not, replace the injector.
- 4With the key on, check for voltage at the injector connector; it should be 12V. If there’s no voltage, trace back to the ECM or fuse.
- 5If all ranges check out, consider testing or reprogramming the ECM.
Common causes
- Faulty fuel injector
- Damaged wiring or connectors
- Failed engine control module (ECM)
- Poor ground connections
- Shorted or open injector circuit
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not a major risk, but you'll have reduced power and fuel efficiency. Fix it soon.
Will this code come back after resetting?
If the underlying issue isn’t resolved, yes, it will likely come back.
Why do I see this with other injector codes?
The injector circuit issue often presents alongside other cylinder issues because it suggests general injector circuit integrity problems.
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