P2052 - Reductant Injection Valve Circuit High Bank 2 Unit 1
The P2052 code indicates a high voltage condition in the reductant injection valve circuit for Bank 2, Unit 1. This valve is part of the Selective Catalytic Reduction (SCR) system, which injects diesel exhaust fluid (DEF) into the exhaust stream to reduce NOx emissions. A high circuit signal typically means the valve or its wiring has a short to voltage, an open circuit, or a faulty control module. This can prevent proper DEF injection, leading to increased emissions and potential derate of engine power.
01. Most Common Causes
- Faulty reductant injection valve
- Short to voltage in wiring or connector
- Open circuit in the valve harness
- Corroded or damaged connector pins
- Failed engine control module (ECM) or SCR control module
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or derate mode
- Increased diesel exhaust fluid consumption
- Failed emissions test
- Possible white smoke from exhaust
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data.
Step 2: Visually inspect the reductant injection valve connector and wiring for damage, corrosion, or loose connections.
Step 3: Using a multimeter, check for voltage at the valve connector with key on. Should be battery voltage (12V) on one pin and ground on the other. If voltage is higher than expected, suspect a short to voltage.
Step 4: Measure resistance across the valve solenoid. Typical resistance is 2-10 ohms. If open or shorted, replace the valve.
Step 5: If wiring and valve are okay, test the ECM/SCR module output by backprobing the connector. If no signal, module may be faulty.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances. The vehicle may enter derate mode, reducing power and potentially causing further damage to the SCR system. Additionally, emissions will be higher.
How much does it cost to fix?▼
The cost typically ranges from $150 to $400, including parts and labor. The reductant injection valve itself costs $50-$150, and labor is about $100-$250 depending on vehicle accessibility.