P2EAF: Reductant Injection Valve Stuck Closed Bank 1 Unit 2

What it means

The reductant injection valve on bank 1 unit 2 is stuck closed. No DEF/AdBlue can be dosed on this unit.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test
• The engine or gearbox may go into limp mode

How it works

The reductant injection valve on bank 1, unit 2 should open to dose DEF/AdBlue into the exhaust treatment system. This code sets when the valve remains closed and cannot dose that unit, potentially because it has seized or deposits are blocking its movement.

Common causes

Most likely first.

1. Valve mechanically seized closed
2. DEF crystallization blocks valve
3. Carbon or debris buildup preventing free movement

Symptoms

• Check engine light or NOx warning on
• AdBlue/DEF level or quality warning
• Possible no-start countdown after ignore period
• Failed emissions inspection (NOx)

How to diagnose it

1. Record freeze-frame data and scan for reductant-pressure, dosing, and NOx codes that could explain why the bank 1 unit 2 valve is not dosing.
2. Inspect the bank 1 unit 2 valve connector and wiring for damage, corrosion, loose terminals, or signs of fluid intrusion.
3. Check the valve tip and nearby passage for DEF/AdBlue crystals, carbon, or debris that could physically block it.
4. Use an approved scan-tool actuation test and compare the valve's commanded operation with its response.
5. If the valve remains closed, test its circuit and supply conditions against the manufacturer's procedure before confirming mechanical seizure.

Common fixes

• Remove deposits from the bank 1 unit 2 valve and dosing passage using an appropriate service method.
• Repair a damaged wire or poor connection at the valve.
• Clear a restriction in the supply to the bank 1 unit 2 valve.
• Replace the valve if it remains mechanically stuck closed after deposits and circuit faults are ruled out.

Can I keep driving?

The engine may keep running, but the affected exhaust treatment system cannot dose correctly, increasing NOx emissions and potentially triggering a no-start countdown. Arrange repair promptly and follow any countdown warning.