What causes fault code P0268?

• Most likely: Short to voltage in the wiring harness for injector 3 • Likely: Faulty fuel injector (internal solenoid short circuit) • Possible: Corroded or damaged connector causing an electrical bridge • Rare: Failed injector driver circuit within the Engine Control Module (ECM)

How do you fix fault code P0268?

STEP 1: Visually inspect the injector 3 connector for corrosion, moisture, or pushed-out pins. STEP 2: Perform a resistance test on the injector using a multimeter. Disconnect the injector and measure across the pins. Standard injectors usually show 12–16 Ohms, while Piezo/low-resistance injectors show significantly less. A reading of 0 Ohms indicates a short. STEP 3: Test wiring harness for short to voltage. With ignition ON and injector disconnected, there should not be a constant 12V on the ground-side trigger wire. STEP 4: Use an oscilloscope to monitor the duty cycle. If the signal remains high constantly, look for wiring insulation damage. STEP 5: Replace injector if internal resistance is out of spec. Perform injector coding/relearn if required by the OEM.

Powertrain (Engine & Gearbox)Standard EOBD

P0268 - Cylinder 3 Injector Circuit High

Q: What are the symptoms of fault code P0268?

• Check engine light (MIL) illuminated • Engine misfiring (Cylinder 3 inactive or erratic) • Excessive exhaust smoke or raw fuel smell • Reduced engine power (Limp mode) • Rough idle and poor acceleration

Last updated:1 February 2026

Related:Fuel Injector Cylinder 3, Engine Control Module (ECM), Kablage / Ledningsnett, Engine Control Relay

System

Powertrain (Engine & Gearbox)

Related Fault Codes

P0200

Injector Circuit Malfunction

P0201

Cylinder 1 Injector Circuit Open

P0202

Injector Circuit - Cylinder 2 - Malfunction

P0203

Injector Circuit - Cylinder 3

Technical Description

P0268 is set when the Engine Control Module (ECM) detects a high voltage condition within the fuel injector control circuit for cylinder 3. The ECM monitors the injector circuit for specific current and voltage peaks. If the voltage remains high when the injector driver should be low (off), the ECM interprets this as a short to voltage. This is typically caused by a shorted wiring harness or an internal short-circuit in the injector solenoid itself. This code will trigger Limp Mode in many modern diesel and petrol systems to protect the catalytic converter or DPF.

Possible Causes

Short to voltage in the wiring harness for injector 3

Faulty fuel injector (internal solenoid short circuit)

Corroded or damaged connector causing an electrical bridge

Failed injector driver circuit within the Engine Control Module (ECM)

Symptoms

Check engine light (MIL) illuminated

Engine misfiring (Cylinder 3 inactive or erratic)

Excessive exhaust smoke or raw fuel smell

Reduced engine power (Limp mode)

Rough idle and poor acceleration

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P0268 - Cylinder 3 Injector Circuit High

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P0268 - Cylinder 3 Injector Circuit High

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