Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 1
The P202E code indicates that the powertrain control module (PCM) has detected a range or performance issue in the reductant injection valve circuit for Bank 1, 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. The PCM monitors the valve's electrical circuit and performance; if the resistance, voltage, or response time is out of expected range, this code sets. Common causes include a faulty reductant injection valve, wiring issues, or a defective PCM.
01. Most Common Causes
- Faulty reductant injection valve
- Open or shorted wiring in the valve circuit
- Poor electrical connection at the valve connector
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance or limp mode
- Increased exhaust emissions
- Possible DEF system warnings
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the reductant injection valve and wiring for damage or corrosion.
Step 3: Test the valve's resistance with a multimeter; compare to manufacturer specs.
Step 4: Check for voltage and ground at the valve connector with the ignition on.
Step 5: If wiring and valve are okay, test the PCM output or replace the valve.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can lead to reduced performance, increased emissions, and potential damage to the SCR system. The vehicle may enter limp mode.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on whether the valve or wiring needs replacement. Parts alone can be $30-$100.