Fuel and air

P0295 — Cylinder 12 Injector Circuit High

Severity: medium Drive with care, to a shop

What P0295 means

The engine control module fires the cylinder 12 injector by switching its circuit to ground and monitors the voltage and current in that circuit. P0295 sets when the signal reads higher than expected. Typical causes are a failed injector, damaged wiring or a fault in the ECM's injector driver. The code only applies to engines with at least 12 cylinders.

Symptoms

  • Check Engine light on
  • Rough idle
  • Misfire or no fuel delivery on cylinder 12
  • Loss of power and hesitant acceleration
  • Higher fuel consumption
  • Hard starting or surging while driving

Possible causes

  1. Failed cylinder 12 injector (internal short or coil fault)
  2. Damaged or corroded wiring and connector terminals in the injector circuit
  3. Injector wire shorted to positive voltage
  4. Poor ground or weak electrical connection
  5. Faulty injector driver inside the ECM

How to diagnose

  1. Read codes and freeze frame data and look for other injector codes
  2. Inspect the cylinder 12 injector connector and harness for damage, moisture and corrosion
  3. Measure injector coil resistance and compare it with the spec and with neighboring injectors
  4. Test the circuit for a short to power and for wire continuity back to the ECM
  5. Check supply voltage and ground at the injector connector
  6. Swap the injector with a known good one and see whether the code follows
  7. Review fuel trims and cylinder balance, and check fuel pressure
  8. If the injector and wiring are good, test the ECM driver

Common fixes

  • Replace the cylinder 12 injector
  • Repair or replace the damaged wiring and connector
  • Fix the short to power and restore the ground
  • Repair or replace the ECM if it is confirmed faulty

Questions and answers

What does P0295 mean?

It means the cylinder 12 injector circuit is reading high. The ECM sees too much voltage or current, most often from a bad injector or wiring.

Can I drive with P0295?

Only briefly and carefully, for example to a shop. Misfires can damage the catalytic converter, and power and fuel economy will suffer.

How do I fix P0295?

Start by checking the wiring, connector and injector resistance. Replacing the injector or repairing the harness fixes most cases, and the ECM is a less common cause.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.