P0289

Cylinder 10 Injector Circuit Low

Powertrain Fuel and Air Metering Fuel Injector Circuit 🟡 Moderate — Fix within a week ⚠️ Drive with Care
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What This Actually Means

In plain language — no jargon

The engine computer detected that cylinder 10's fuel injector isn't receiving enough electrical current to operate properly. It's like a light switch that's getting a weak signal and can't fully turn on.

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Symptoms You May Notice

3 known symptoms for this code
Engine misfire or rough idle on cylinder 10
Reduced fuel economy and power loss
Check Engine Light illuminated
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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECM monitors the voltage and current flowing through the cylinder 10 injector circuit during activation. When the injector fires, the ECU expects to see a voltage drop and sustained current flow within specified parameters. If the measured current falls below the minimum threshold, the fault is logged.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Injector Circuit Current 2.0-4.5 amps during pulse Below 1.5 amps or open circuit detected
Injector Control Voltage 12V supply with PWM modulation Voltage sag or failure to reach operating threshold
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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex
1
Fuel injector connector and wiring harness
Inspect and clean the connector on cylinder 10's injector for corrosion or loose pins, then reconnect firmly.
2
Fuel injector (cylinder 10)
Replace the injector if connector cleaning doesn't resolve the issue, as internal resistance may be too high.
3
Engine Control Module (ECM) injector driver circuit
Have the ECM tested or replaced if wiring and injector are confirmed good, as the driver transistor may be failing.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code P0289 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.

Safety note: OBD-II codes identify the system or circuit where a fault was detected — they do not always identify the exact failed component. A professional mechanic using live sensor data will diagnose the root cause more accurately than replacing parts based on the code alone.
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How to Clear Code P0289

What happens after you fix the fault

Once the fault is repaired, P0289 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.

The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.

✅ Safe to Clear When
  • Fault has been diagnosed and repaired
  • You want to confirm the repair worked
  • Code appeared after a sensor was cleaned
⚠️ Do Not Clear When
  • Preparing for an emissions/PUC test
  • Root cause is still undiagnosed
  • Check engine light is flashing
Emissions test note: Clearing codes resets OBD readiness monitors. Most vehicles need 50–100 km of mixed driving before monitors complete. Do not clear codes immediately before an emissions or PUC inspection.