P0261

Cylinder 1 Injector A Circuit Low

Fuel injector circuit Generic OBD-II High

What it means

P0261 means the ECM has detected low voltage — typically a short to ground — in the control circuit for the cylinder 1 fuel injector. If the circuit fails, cylinder 1 stops firing and the engine misfires, runs rough, and loses power. The usual cause is shorted wiring, a bad connector, or a failed injector.

High

Can I keep driving? Drive as little as possible — a low-voltage/short fault in the cylinder 1 injector circuit can kill that cylinder, causing a heavy misfire, rough running and possible stalling.

Real-world scan data

Seen in

379

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0261 scans

P0264in 55.1% of scans

P0267in 48.8% of scans

P0270in 45.6% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Misfire, rough idle, or shaking from a dead or weak cylinder 1
Reduced power and hesitation on acceleration
Rough running and, on some engines, stalling

Common causes

Most likely first

Injector control wire shorted to ground (most common for a 'low' code)Likely
Corroded, loose, or damaged connector at the cylinder 1 injectorCommon
Failed fuel injector with a shorted coilCommon
Faulty ECM injector driver (rare)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame and confirm the circuit-low/injector fault is on cylinder 1.
Inspect the injector wiring and connector for a short to ground, chafing, or corrosion.
Measure the injector coil resistance against spec and compare with a known-good cylinder.
Swap the suspect injector with a neighbouring one; if the fault follows, replace the injector.
Verify the ECM's injector driver is functioning before condemning it, then clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0261?+

Keep it brief. A dead cylinder 1 means a heavy misfire that wastes fuel and can overheat the catalytic converter, so fix it promptly.

Can I just clear P0261?+

It returns as soon as the short or injector fault is seen again. Repair the wiring or injector first, then clear it.

Read & clear P0261 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

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✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX