P0289 Injector: signal or voltage too high (cylinder 10)

By: Diagno editorial team · Updated: 2026-10-15

P0289 means: Injector: signal or voltage too high (cylinder 10). The injector sprays fuel into the cylinder. Drive gently and have the car checked soon. The repair usually costs about €60–300 in Estonia. The most common cause: connector loose, damp or corroded. Other possible causes: wire shorted to power or ground broken, faulty injector.

What it means

The injector sprays fuel into the cylinder. The computer found a fault in the injector control or its fuel quantity. The signal voltage is too high. Usually a wire is shorted to power, the ground is broken or the part itself has failed.

What you may notice

• Engine light on
• The engine runs unevenly
• Less power
• Higher fuel consumption

What could be wrong

1. 1Connector loose, damp or corroded
2. 2Wire shorted to power or ground broken
3. 3Faulty injector
4. 4Engine computer fault (rare)

Repair difficulty: Moderate

What you can check yourself

First look at the connector and wiring: anything loose, melted or green with corrosion? Check the injector connectors. If the engine runs badly on one cylinder, don't drive far. Best left to a workshop. It needs a diagnostic tool and experience.

How we fix it

1. We read the fault data on the diagnostic tool and check whether the fault is constant
2. We measure the circuit's supply, ground and signal
3. We repair the wire or replace the connector
4. If the wiring is fine, we replace the injector

Standard SAE description: Cylinder 10 Injector Circuit High