Reductant Injection Valve Circuit/Open Bank 2 Unit 1
The reductant injection valve circuit on Bank 2 is open or has a continuity problem, preventing proper operation of the selective catalytic reduction (SCR) system. This code indicates an electrical fault in the valve circuit that must be addressed to prevent catalyst damage and maintain emissions compliance.
What You Might Notice
- Diminished engine performance
- Excessive black smoke from exhaust
- Reduced fuel efficiency
- Check engine light illuminated
- Other SCR-related fault codes present
Most Common Causes
- 1
Faulty reductant injection valve
The solenoid valve itself may be defective or stuck, preventing electrical current from properly activating the valve mechanism.
- 2
Wiring or connector issues
Open circuit, broken wires, corroded connectors, or loose connections in the valve circuit harness can cause loss of continuity to the valve.
- 3
ECU or control module fault
The engine control unit may have a defective driver circuit for the reductant valve, preventing it from sending proper command signals.
- 4
Reductant system contamination or blockage
Crystallized or contaminated reductant fluid may prevent valve operation, though this typically causes pressure codes rather than open circuits.
How to Diagnose It
- 1
Check Faulty reductant injection valve — The solenoid valve itself may be defective or stuck, preventing electrical current from properly activating the valve mechanism.
- 2
Check Wiring or connector issues — Open circuit, broken wires, corroded connectors, or loose connections in the valve circuit harness can cause loss of continuity to the valve.
- 3
Check ECU or control module fault — The engine control unit may have a defective driver circuit for the reductant valve, preventing it from sending proper command signals.
- 4
Check Reductant system contamination or blockage — Crystallized or contaminated reductant fluid may prevent valve operation, though this typically causes pressure codes rather than open circuits.
How to Fix It
- 1
Test and repair valve wiring
Inspect the reductant injection valve harness and connectors for corrosion, loose pins, or broken wires. Use a multimeter to verify continuity and proper voltage at the valve connector when ignition is on.
- 2
Replace reductant injection valve
If wiring and connectors are sound, the valve solenoid is likely defective and must be replaced. Install new valve and clear the code to verify the repair.
- 3
Check ECU control circuits
Use diagnostic equipment to test the ECU's output driver circuit for the reductant valve. If the ECU cannot provide proper signal voltage, the module may require reprogramming or replacement.
- 4
Flush and refill reductant system
Drain old reductant fluid, flush the system lines and tank with clean solution, and refill with fresh manufacturer-approved reductant to eliminate potential blockages.
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