P0286
Cylinder 9 Injector A Circuit High
Fuel injectors
Generic OBD-II
High
What it means
P0286 means the ECM has detected an abnormally high voltage (or an open) in the cylinder 9 fuel-injector control circuit. This code appears on larger engines with nine or more cylinders. When that injector can't be driven properly, cylinder 9 misfires, so the engine runs rough and loses a little power. The cause is usually electrical — the injector coil, its connector, or the wiring.
High
Can I keep driving? You can drive short-term, but cylinder 9 may misfire; a sustained misfire wastes fuel and can overheat the catalytic converter, so fix it soon.
Common symptoms
What you'll notice
- Check-engine light on
- Rough idle or a cylinder-9 misfire
- Reduced power and hesitation
- Increased fuel consumption, possible fuel smell
- Companion misfire code P0309
Common causes
Most likely first
- Open or high-resistance in the cylinder 9 injector control circuitLikely
- Failed cylinder 9 injector (open or high-resistance coil)Common
- Corroded or loose injector connectorCommon
- Damaged wiring or a weak ECM injector driverLess often
- ECM fault (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for a cylinder-9 misfire code (P0309).
- Inspect the cylinder 9 injector connector and wiring for opens or high resistance.
- Measure the injector's coil resistance and compare it to specification.
- Swap or replace the injector, or repair the wiring.
- Clear the code and re-test.
FAQ
Quick answers
Is it safe to drive with P0286?+
For short trips, but cylinder 9 may not fire properly. A prolonged misfire dumps raw fuel into the exhaust and can damage the catalytic converter, so repair it soon.
Can I just clear P0286?+
It returns as soon as the injector circuit faults again. Fix the injector or wiring rather than clearing the code.
Related codes
Often seen with P0286
Read & clear P0286 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX