P0289 indicates that the powertrain control module (PCM) has detected a voltage higher than expected on the fuel injector control circuit for cylinder 10. This usually points to a short to battery voltage in the injector wiring, connector, or the injector itself, though a faulty injector driver in the PCM is possible but uncommon.
The injector coil or internal diode may be shorted to battery voltage, causing the PCM to see an excessively high voltage on the control circuit.
A chafed or damaged wire in the injector circuit for cylinder 10 may be contacting a power source, producing a high‑voltage signal to the PCM.
Poor contact or corrosion at the injector connector can create an abnormal voltage reading that the PCM interprets as a circuit high condition.
Although uncommon, a failure in the PCM’s injector driver circuit for cylinder 10 can cause a false high‑voltage reading; this should be considered only after wiring and injector are verified good.
No. The PCM is rarely at fault for this code; most cases are caused by a shorted injector, wiring issue, or connector problem. Replacing the PCM without first checking those components often does not resolve the code.
No. P0289 is specific to the injector circuit high voltage; spark‑plug issues produce misfire codes (P030x) but do not affect the injector voltage reading.
It indicates the original injector is faulty (shorted internally) because the fault followed the injector to the new cylinder location.
With the key on and engine off, the injector control wire should read near 0 volts (ground) when the PCM is not commanding the injector; any significant voltage suggests a short to power.