P20B8 Code - Diesel Exhaust Fluid Reductant Pump Heater Control Circuit High
Quick Answer
The P20B8 diagnostic trouble code indicates a problem with the Diesel Exhaust Fluid (DEF) Reductant Pump Heater Control Circuit being too high. Common causes include Malfunctioning Reductant Pump Heater: The heater itself may be faulty and not functioning properly, causing the high voltage condition, Faulty Wiring: A short circuit or damaged wiring in the heater circuit can also trigger this code, Defective Relay: A malfunctioning relay that controls the reductant pump heater may cause the high voltage condition. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P20B8 indicates Diesel Exhaust Fluid Reductant Pump Heater Control Circuit High.
- Common causes
- Common causes include Malfunctioning Reductant Pump Heater: The heater itself may be faulty and not functioning properly, causing the high voltage condition, Faulty Wiring: A short circuit or damaged wiring in the heater circuit can also trigger this code, Defective Relay: A malfunctioning relay that controls the reductant pump heater may cause the high voltage condition.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P20B8 Description
The P20B8 diagnostic trouble code indicates a problem with the Diesel Exhaust Fluid (DEF) Reductant Pump Heater Control Circuit being too high. In vehicles equipped with Selective Catalytic Reduction (SCR) systems, DEF is injected into the exhaust stream to reduce harmful emissions. The reductant pump heater is responsible for maintaining the DEF at the optimal temperature for efficient operation.
Common Causes of P20B8
- Malfunctioning Reductant Pump Heater: The heater itself may be faulty and not functioning properly, causing the high voltage condition.
- Faulty Wiring: A short circuit or damaged wiring in the heater circuit can also trigger this code.
- Defective Relay: A malfunctioning relay that controls the reductant pump heater may cause the high voltage condition.
- Control Module Issue: A problem with the control module that monitors the reductant pump heater circuit can also lead to this code being triggered.
Symptoms of P20B8
- Check Engine Light: The most common symptom associated with this code is the illumination of the check engine light on the vehicle's dashboard.
- Reduced Power: The vehicle may experience a decrease in power or performance due to the malfunctioning reductant pump heater.
- Poor Fuel Economy: A faulty reductant pump heater can lead to poor fuel efficiency as the SCR system may not be operating optimally.
- Failed Emissions Test: If the issue is not addressed, it may cause the vehicle to fail emissions testing due to increased emissions.
How to Fix P20B8
- Diagnose the Issue: Use a diagnostic scanner to retrieve the trouble code and determine the exact cause of the problem.
- Inspect Wiring and Connections: Check the wiring and connections in the reductant pump heater circuit for any damage or corrosion.
- Test the Reductant Pump Heater: Verify the functionality of the reductant pump heater to see if it is operating correctly.
- Replace Faulty Components: Replace any faulty components such as the heater, relay, or control module as needed.
- Clear Codes and Test Drive: Once the repair is completed, clear the trouble codes from the vehicle's memory and test drive to ensure the issue has been resolved.
Cost to Fix P20B8
The cost of repairing a P20B8 code can vary depending on the extent of the issue and the specific components that need to be replaced. On average, the repair for this issue can range from $200 to $500. This cost includes parts and labor. It's important to note that diagnostic time and labor rates at auto repair shops can vary, so it's advisable to check with local shops for a more accurate estimate.
Need more information about the P20B8 code?
Need more information on how to fix the P20B8 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P20B8 code diagnosed by a professional: Find a repair shop in your area
Code P20B8 Information for Specific Makes
- P20B8 Dodge — Diesel Exhaust Fluid Reductant Pump Heater Control Circuit High
- P20B8 RAM — Diesel Exhaust Fluid Reductant Pump Heater Control Circuit High
Frequently Asked Questions about P20B8 Code
No Frequently Asked Questions about P20B8 Code found.
Discuss the causes and fixes for P20B8 OBDII Code
Code P20B8 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.