The P20B6: Reductant Metering Unit Heater Control Circuit Performance refers to a problem with the performance of the metering unit heater control circuit. This means the heater may not be functioning as efficiently as expected, potentially due to faults in the heater itself or the control module that manages it.
P20B6 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20B6: Reductant Metering Unit Heater Control Circuit Performance |
| Is it serious? | Yes, this can affect the performance of the reductant system, which may lead to emissions-related problems. |
| Possible causes | – Metering unit heater performance issues – Faulty heater – Faulty control module |
| How to diagnose? | – Test the performance of the metering unit heater – Inspect for faults in the heater – Check the control module functionality |
P20B6 Meaning
The P20B6 fault code indicates that there is a performance issue with the control circuit for the reductant metering unit heater. This could mean that the heater is not working as it should, which may affect the system’s ability to properly manage emissions. This can be caused by a faulty heater or a malfunction in the control module.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check if any additional codes are present that could provide further insights into the issue. | OBD-II Scanner |
| Test the Metering Unit Heater Performance | Use a diagnostic tool to test the performance of the metering unit heater. Compare the results with manufacturer specifications. | Multimeter, Diagnostic Tool |
| Inspect the Heater | Visually inspect the metering unit heater for any signs of wear, damage, or malfunction. | Flashlight, Multimeter |
| Check the Control Module | Use a diagnostic tool to verify the functionality of the control module to rule out module-related issues. | Diagnostic Tool |
| Repair or Replace Heater | If the heater performance is below specification, repair or replace the metering unit heater. | Replacement Heater, Tools |
| Clear the Code and Test Drive | After repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to confirm that the issue is resolved. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | Rescan the vehicle after the test drive to ensure the P20B6 code has not returned. | OBD-II Scanner |
OBD-II scanner Buyer’s Guide
- Scanner features explained
- Different types of scanners
- Scanners for coding/odometer/ECU/checks
- Best picks + discount codes
Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)