P269A: Exhaust Aftertreatment Fuel Injector A Circuit High

What it means

Voltage on the 7th injector control line is above the expected window. Typical causes are a short to battery or an open solenoid coil.

At a glance

• Usually lights the check-engine light

How it works

Injector A doses fuel into the exhaust during active DPF regeneration to help raise exhaust temperature. P269A sets when the controller detects voltage on this injector's control circuit above its expected range, which can result from a short to battery, an open injector coil, or a poor connection.

Common causes

Most likely first.

1. Control wire shorted to B+
2. Open injector coil
3. Connector pins corroded - high contact resistance

Symptoms

• Check-engine light
• DPF warning light
• More frequent or unsuccessful DPF regeneration

How to diagnose it

1. Check freeze-frame data and regeneration history to determine whether the high-circuit fault appeared during a dosing command.
2. Inspect injector A's connector and harness for heat damage, chafing, corrosion, or a loose terminal.
3. With the circuit safely de-energized as specified by the manufacturer, test the injector coil for an open circuit.
4. Test the control wire for a short to battery voltage and inspect connector contact quality using the vehicle wiring diagram.
5. If the injector and wiring are sound, check the controller driver and circuit readings against manufacturer specifications.

Common fixes

• Repair a loose or corroded injector A connector or terminal.
• Repair wiring shorted to battery voltage or damaged insulation.
• Replace injector A if its coil is open and fails the specified test.
• Repair the controller driver only after confirming the injector and harness are in good condition.

Can I keep driving?

Drive cautiously if the vehicle otherwise runs normally, while avoiding repeated short trips and monitoring the DPF warning. If regeneration cannot dose fuel, soot can continue to accumulate and may lead to reduced power or a blocked filter.