OBD-II Code · Fuel & Air
P0279
Cylinder 7 Injector Circuit Low
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)
$55–$510
Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
Cyl 7 injector shorted to ground.
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
- Misfire cyl 7
- Check engine light
Likely causes
- Shorted injectorMost common
- Harness short
Read the full diagnostic procedureP0279 means the cylinder 7 injector circuit is reading low, which the PCM interprets as a short to ground or an internally shorted injector solenoid.
P0279 means the cylinder 7 injector circuit is reading low, which the PCM interprets as a short to ground or an internally shorted injector solenoid. Start cheap by pulling injector 7 and swapping with a known-good unit; if the code follows the injector it is internally shorted.
Bench-ohm both injectors
PFI saturated should be 11 to 17 ohms cold, GDI solenoid 1.5 to 4 ohms cold; a shorted PFI winding typically reads 4 to 9 ohms, and a shorted GDI winding reads under 1 ohm. With the harness side disconnected and key on, the driver pin should read open (high impedance) to ground; a driver pin reading 0 to 0.5 ohms to chassis ground is a harness short. Caveat: on Chrysler MDS-equipped 5.7L Hemi engines, cylinder 7 is one of the deactivated cylinders, so the injector sees longer dwell off-times and any marginal winding will fail there first, masking a fleet-wide injector quality issue.
Vehicle-specific patterns2005 to 2010 Dodge Ram 1500 5.7L Hemi commonly throws P0279 from cracked injector solenoid windings on the deactivating cylinders, Mopar TSB 18-040-0…
- 2005to 2010 Dodge Ram 1500 5.7L Hemi commonly throws P0279 from cracked injector solenoid windings on the deactivating cylinders, Mopar TSB 18-040-07;
- 2007to 2013 Chevrolet Silverado 5.3L AFM trucks see the same pattern on cylinder 7 due to active fuel management dwell stress;
- 2005to 2008 Ford Mustang GT 4.6L 3V has harness chafe at the rear bank near the firewall heater pipe.
Estimated repair$55 to $510.
Look up another code
P0279 — frequently asked
What does a P0279 code mean?
Cyl 7 injector shorted to ground.
What causes a P0279 code?
Common causes: Shorted injector; Harness short.
What are the symptoms of a P0279 code?
Typical symptoms: Misfire cyl 7; Check engine light.
Is it safe to drive with a P0279 code?
Not for long. Driving on this one risks further damage. Get it to a shop rather than carrying on with it. Estimated repair: $55-$510.
How do I diagnose a P0279 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.
More free tools