Reductant Temperature Sensor Circuit Intermittent
The P2046 code indicates that the powertrain control module (PCM) has detected an intermittent signal from the reductant temperature sensor, which monitors the temperature of diesel exhaust fluid (DEF) in the selective catalytic reduction (SCR) system. This sensor is critical for proper DEF injection and emissions control. An intermittent circuit fault may be caused by a loose or corroded connector, damaged wiring, or a failing sensor. If left unaddressed, it can lead to reduced engine performance, increased emissions, and potential damage to the SCR system.
1. Most Common Causes
- Loose or corroded electrical connector at the reductant temperature sensor
- Damaged or chafed wiring in the sensor circuit
- Faulty reductant temperature sensor
- Intermittent short or open in the sensor circuit
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or limp mode activation
- Increased diesel exhaust fluid consumption
- Failed emissions test
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes (e.g., P2047-P2052).
Step 2: Visually inspect the reductant temperature sensor connector and wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor resistance and compare to manufacturer specifications; replace if out of range.
Step 4: Check for intermittent shorts or opens by wiggling the wiring harness while monitoring sensor signal with a scan tool.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code, as it can cause the SCR system to malfunction, leading to increased emissions and potential engine derating. You may experience reduced power and fuel economy.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on whether the issue is a simple connector fix or requires sensor replacement. Sensor replacement parts cost around $30-$80, plus labor.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.