Fuel and air

P0289 — Cylinder 10 Injector Circuit High

Severity: medium Drive with care, to a shop

What P0289 means

The engine control module fires each injector by switching its circuit to ground, and it monitors voltage and current in that circuit. P0289 sets when the cylinder 10 injector circuit reads higher than expected. Typical causes are a short to voltage, a failed injector coil, or a faulty driver inside the control module. The code applies to engines with ten or more cylinders.

Symptoms

  • Check engine light on
  • Rough idle or engine vibration
  • Loss of power and weak acceleration
  • Misfire on cylinder 10
  • Higher fuel consumption
  • Hesitation under load

Possible causes

  1. Damaged wiring harness for injector 10 (short to voltage)
  2. Faulty injector 10 (internal short or excessive current draw)
  3. Corroded or loose connector at the injector
  4. Failed injector driver in the PCM
  5. Chafed or heat-damaged wire insulation
  6. Poor previous repairs or aftermarket wiring

How to diagnose

  1. Scan all codes and freeze-frame data, and note any other injector or misfire codes
  2. Inspect the injector 10 connector and harness for heat damage, chafing, corrosion or oil
  3. Make sure the connector seats firmly and clean the terminals
  4. Measure injector 10 coil resistance and compare it with the specification and neighboring injectors
  5. Test the injector wires for shorts to voltage and ground
  6. Check the injector control pulse with a scope or noid light
  7. Swap the injector with a neighboring cylinder: if the fault follows, the injector is bad
  8. If wiring and injector are fine, check power supply and the PCM driver

Common fixes

  • Repair or replace the damaged harness section and connector
  • Replace the faulty cylinder 10 injector
  • Repair or replace the PCM if the driver has failed
  • Clear codes and road test to confirm the code does not return

Questions and answers

What does P0289 mean?

The PCM sees a too-high signal in the electrical circuit of the cylinder 10 fuel injector. Wiring, the connector or the injector itself are the usual culprits.

Can I drive with P0289?

Only briefly and carefully, to a repair shop. The cylinder may misfire, which reduces power and stresses the catalytic converter, so don't put the repair off.

How do I tell an injector fault from a wiring problem?

Measure the injector resistance and test the wires for shorts. If the wiring is fine and the injector is out of spec, or the fault moves with it when swapped to another cylinder, replace the injector.

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.