OBD-II fault code

P0280: Cylinder 7 Injector Circuit High

What it means

The control module detects a high condition in the cylinder 7 injector circuit. This indicates an electrical circuit fault and does not by itself establish an injector flow problem.

At a glance

  • Usually lights the check-engine light
  • Affects emissions; the car can fail an emissions test

How it works

The control module monitors the electrical circuit that operates the cylinder 7 fuel injector. This code sets when the circuit signal is higher than expected, which can indicate a short to battery voltage; it does not prove that the injector is flowing too much fuel.

Common causes

Most likely first.

  1. Wiring shorted to battery
  2. Connector pins corroded - high contact resistance
  3. Supply wire pinched against B+ source

Symptoms

  • Check-engine light
  • Rough idle or misfire
  • Reduced power
  • Increased fuel consumption

How to diagnose it

  1. Use freeze-frame data and live misfire information to note when the fault occurs and whether cylinder 7 is affected.
  2. With the engine off, inspect the cylinder 7 injector connector and harness for pinched insulation, chafing, corrosion, or contact with a power source.
  3. Check the cylinder 7 injector circuit for a short to battery voltage using the vehicle wiring diagram and the manufacturer's test procedure.
  4. Check connector continuity and terminal contact, comparing results with the manufacturer's specification.
  5. If the wiring and connections pass, test the injector and its control circuit before deciding whether the injector itself has failed.

Common fixes

  • Repair cylinder 7 injector wiring shorted to a power source.
  • Repair corroded or loose connector terminals.
  • Secure or reroute a pinched supply wire away from battery voltage.
  • Replace the cylinder 7 injector only if testing confirms it is faulty.

Can I keep driving?

If the engine runs smoothly, a short, gentle trip may be possible, but avoid heavy loads because a cylinder 7 misfire can damage the catalytic converter. Stop if it misfires severely, stalls, or loses power.

A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together

This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.

Codes for the same component